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Best mulches for orchards

Posted by MrsG47 7 RI (My Page) on
Fri, Jan 17, 14 at 11:13

My neat little paths around my mulched trees is becoming a 'pain in the neck' maze for mowing during the summer months. It looks very nice when mowed and there are nice paths around the orchard, but my mower is screaming uncle!

I have been using plain black pine bark for mulch. Is there a better mulch to use as I am thinking of mulching the entire orchard, or is this a bad idea? Many thanks, Mrs. G


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RE: Best mulches for orchards

  • Posted by murky z8f pnw Portlan (My Page) on
    Fri, Jan 17, 14 at 13:53

Free wood chips from arborist, utility company or tree trimming service.


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RE: Best mulches for orchards

Mrs. G.

How big is your orchard? The area I planted most of my fruit trees is about 20-35 ft rectangle.

Last year, I got sick of weeds, I mulched the entire area. To be corrected, I had someone mulched it for me. He put weed barrier down first before mulching.

I don't like the only tree trimming company in town. My guy who did the work has a good deal with the place he got the mulch. I used hemlock mulch.


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RE: Best mulches for orchards

  • Posted by fruitnut z7b-8a,4500ft SW TX (My Page) on
    Fri, Jan 17, 14 at 17:58

I don't like fighting weeds either so I've put down black weed barrier on much of my outside orchards. But I get 15 inches rain in a good year and have very nitrogen deficient soil. With all that organic mulch and high rainfall you're set up for rampant growth and possibly diminished fruit quality. Are you considering that possibility?


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No Fruitnut, I hadn't thought of that. I guess I will lay down black weed barrier around the trees and cover the five foot square with mulch. It will be easier for mowing if the mulch is in squares instead of circles. I would really like to get metal edging around each tree then mulch, but I am concerned about the cost and installation. I will at least move out of circles of mulch around my trees and mulch onto squares and rectangles. Most of the nitrogen my trees get is from lawn fertilizer. I would prefer fruit quality. Thanks for all of your thoughts. As for size of my orchard, it is over 50' in depth; I've never measured the width. Mrs. G


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RE: Best mulches for orchards

Fruitnut,
I've never thought of such rampant growth, either. This year, I'll find out. I'll keep watch. Thanks for the warning.

Mrs. G. - your orchard probably 2-3 times bigger than mine. Before I know about spacing, I cramped a lot of fruit trees in the area. It's too late to move them. Pruning is what I will need to get a good handle on.


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Mamuang, unfortunately I have more room for trees, but I'll stop for a while.

Fruitnut, if mulching my entire orchard will deprive it of nitrogen and induce prolific growth, then how, under a high tunnel with ground cover, do you not have the same problem? Thanks Mrs. G


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RE: Best mulches for orchards

MrsG, I think he is saying mulching everything could increase the nitrogen levels due to decomposing mulch. This would cause excess nitrogen and excessive vigor and could diminish fruit quality. I would think a five foot ring or square of mulch would cause the same symptoms as a 5 foot ring is about the spread of the roots. I hate weeds as well and have decided to mulch my entire 60x30 foot orchard. I could use a bit of nitrogen and am not worried about excessive nitrogen in the near future. Ease of maintenance is more important to me at the moment. If it becomes an issue later, you could replace the mulch around the trees with something that wouldn't produce as much nitrogen.


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If you are concerned about nitrogen levels due to mulch, maybe you could use a cedar mulch as it breaks down very slowly? Is Cedar mulch ok for an orchard?


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RE: Best mulches for orchards

  • Posted by fruitnut z7b-8a,4500ft SW TX (My Page) on
    Fri, Jan 17, 14 at 21:54

MrsG:

It's not lack of nitrogen that causes rampant growth but rather too much nitrogen together with too much water. A mulch increases water available to the plant and can increase or decrease nitrogen depending on the mulch and it's stage of decomposition.

I don't know how much of an issue this will be. Maybe your plants already have enough water and fertilizer to maximize growth. But nearly all fruit trees and vines at some point kick into overdrive and can grow 5-10ft per year if those factors are present in excess.

Some plants need all the water and N they can get, sweetcorn is a good example. Fruit trees are better grown at moderate to low vigor.

A lot depends on your soil and climate. Some soils are very supportive of vigorous growth others not nearly as much.


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  • Posted by bob_z6 6b/7a SW CT (My Page) on
    Sat, Jan 18, 14 at 1:45

I've got a lot of fruit trees in raised beds made out of tree trunk sections. The beds are all mulched with woodchips, so I don't get too many weeds there. But, I do have problems mowing around it. I've tried just piling the woodchips over the edges and onto the grass, but it makes it pretty tough on the mower (and looks a bit untidy, if that is a concern).

I'm trying a different strategy this spring in a new 40' raised bed (mostly plums). I'll use cement blocks as the material, so it has a nice vertical edge. I've purchased some rolls of 5" wide lawn edging, which I'll lay horizontally, with the edge just barely under the block. I'm hoping that this give me ~3-4" of coverage where no grass/weeds can grow and I can run the wheels of the mower over. I'll let you know how it goes.

I've also been frustrated by garden weeds, so this fall I dug up the 30'x30' garden area (vegtables and strawberries) and made it into raised beds. The wide-open garden approach was proving very difficult to keep weeded, while the beds I had in other parts of the yard were relatively clear. I used both cement blocks and tree trunk sections. In the spring, I'll wood-chip all the paths, which would otherwise be mud.


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Fruitnut and Rawley, thank you so much for defining the nitrogen issue for me. You are both kind to a newbie orchardist. I have a very nasty weed called 'Creeping Charlie', or 'Ground Ivy'. It has overtaken the lawn. When it is mowed it smells like mothballs and is horrible. A nasty fragrance. I thought the area of mulch beneath each tree should reach out to the width of the canopy or drip line of the tree. My Italian Plum, for example, is at least eight feet in diameter (canopy). All of my trees are pruned to no higher than 8-9 feet tall. In this way they are manageable. I had no idea that mulching with five foot squares would create the exact problem of inducing growth instead of quality fruit. What do I do? Thanks Mrs. G
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RE: Best mulches for orchards

  • Posted by olpea zone 6 KS (My Page) on
    Sat, Jan 18, 14 at 14:07

I've used wood mulch in my backyard orchard for quite some time. Although I agree mulch holds water and does increase vigor, I think the fruit flavor is very good on my trees.

Admittedly, they are my trees, which could bias my decision, but I'm trying to look at it objectively based on comments from others.

There are others (including a neighbor with which we share a fence line) who grow peaches and tell me mine are better than theirs. It's possible others are just trying to be nice, but even the neighbors young kids tell me my fruit is better than theirs (which, I'll all add mirrors my own opinion). One difference is my trees are mulched and theirs aren't.

I've had several customers who grow their own peaches and still buy from me, so I don't think it's an anomaly.

I have had quality problems during heavy rain, or if I have mulched very heavy with fresh grass clippings.

I'll defer to Fruitnut on how to get maximum brix, but for overall taste my experience is that a wood chip mulch has little to no effect, and may actually enhance flavor. Possibly because more minor and trace nutrients are available and larger leaf surface for greater photosynthesis.

I think vigor and fruit quality can be a pretty complicated relationship. Too little vigor and not enough photosynthesis, too much and there is too much shading.


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RE: Best mulches for orchards

  • Posted by fruitnut z7b-8a,4500ft SW TX (My Page) on
    Sat, Jan 18, 14 at 14:40

olpea:

My impression is that you have strong soil which would enhance vigor. But you also have a hotter and drier climate than MrsG. I trust your observations and expertise. If you are only having quality issues during rainy periods and when extra nitrogen is applied via grass clippings, then I'd take that to the bank.

I don't want to make too big an issue of this. Especially in light of the fact that I have no idea what anyone else is dealing with in the way of soil, irrigation, climate, etc. Each person has to learn their own situation and deal accordingly.

Personally I'd rather deal with vigor on the low side than the high side. I can, most of the time, increase vigor if needed. But if vigor is out of hand not only is fruit quality possibly lower but pruning and disease pressure are worse.


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Mrsg,
You may want to peruse the Soil, Compost, Mulch forum. There may be no Best mulch for your trees. I use wood chips from tree trimmers, leaves in the fall and all of the weed(plant growing where you don't want them) tops.
Then you could use green manure/mulch as well. Letting your soil food web re-establish itself by not compacting or digging the soil will supply your trees with all of the major/minor nutrients your trees need as well as help with less watering. Unless you live in California or the west this year.


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Options! Wow, you have all helped me so much and I thank you all. Mrs. G


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RE: Best mulches for orchards

  • Posted by mrclint z10SoCal Valley (My Page) on
    Sat, Jan 18, 14 at 20:02

Mulch away to your heart's content. The benefits far out weigh any perceived negatives. I don't see mulch adding much in the way of nitrogen to the soil. As it breaks down it may even lock up some of the N if you use raw wood chips. When mulch breaks down you are left with compost, which is very low in N -- maybe 1%, but probably no higher than 3%.

Here is a link that might be useful: Backyard Fruit Tree Basics: Mulch


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RE: Best mulches for orchards

I believe I brought the question here originally of whether mulch can become a problem overtime when applied annually under fruit trees.

I became suspicious when my healthy and vigorous peach trees became more bland and less flavorful, some after over 15 years of this treatment. By this point I had created about 5 new inches of black, beautiful humus in rings under all my fruit trees.

My native soil isn't very rich and doesn't hold water well and I've since observed that the best, most highly flavored fruit tends to come from the orchards I manage with the sandiest and quickest drying soil.

Overtime, annual mulching with organic materials creates a perfect soil for corn, IMO, but not for fruit trees. Growers in the west have no way to evaluate this affect unless they over irrigate their trees- then the greater richness and water holding capacity of their soil would come into play.

FN is right, proceed with caution on this. I used to keep fruit trees mulched indefinitely but I now tend to let the mowed sod return after trees reach maturity. Mulch is very helpful for establishing trees when highest vigor is useful but once they achieve desired size, you want moderate vigor only. Mulch accordingly, IMO. As long as trees don't become too vigorous, you don't have to worry about using mulch.

I am planning to try broken up marble stone over woven landscape fabric under a few of my established peach trees this season. I'm hoping the added reflected light may be beneficial.

Of course, even an inorganic mulch will increase vigor just by eliminating all competition beneath it but I'm dying to give this method a try.

Incidentally, Olpea lives in a part of Kansas that tends not to get much rain in the summer months- his trees are also still pretty young. How many years have your oldest trees been under mulch, Olpea?

At first mulch removes more N than it adds and it takes quite a bit of time for it to drastically change the nature of the native soil.

For weed control, shredded wood works best, as it forms a mat that can actually repel rain water and helps keeps weeds from popping through- no fabric necessary in average lawn. However, chips out of an arborists truck , Sweetpeet (composted stable waste) or pine bark nuggets works better if you want that rain water to reach the roots of young trees-
probably helps gas exchange as well.

Woven fabric can also cause rain water to flow downhill instead of soaking into the soil. It has slower percolation then the spun stuff.


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RE: Best mulches for orchards

  • Posted by fruitnut z7b-8a,4500ft SW TX (My Page) on
    Sun, Jan 19, 14 at 9:32

Thanks harvestman, your analysis makes perfect sense to me. I'd even agree with the part about woven weed barrier, the kind I use. What I do with that is make level basins. Basin meaning there is a berm around a leveled area. Then I cover all that with the woven weed barrier. This maintains the berm for years, holds the big rains in place, and increases tree growth by increasing water and reducing competition for nutrients. In my situation (lack of rain, weak soil, low nitrogen) that's appropriate for young trees.

I'd rather use wood chips but out here they're not available or too expensive to buy bagged.

If my trees become too vigorous after they start bearing I'll replace the weed barrier with grass to compete with them.


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RE: Best mulches for orchards

  • Posted by glib 5.5 (My Page) on
    Sun, Jan 19, 14 at 10:20

Agree with HM. Relatively poor soil makes the best fruits. Different varieties may be more or less adapted to different soils. Olpea, not only has a too-dry soil, he also has a lot of calcium, and heavy mulching (after turning into humus) helps mitigate that.


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Fruitnut, I do the same thing when I use the woven stuff. In my vegie garden I use it to help control bindweed, which laughs at all organic mulch I've applied- even shredded wood. I make slightly concaved raised beds and then lightly cover the fabric with organic mulch when the weather turns hot. I leave bare fabric between beds. It is treated to be UV resistant, unlike the spun stuff I've used. Lasts a few years.

I make sure to create a similar concave affect before using woven fabric under fruit trees and covering with wood chips, I learned the hard way in an orchard I installed in a seldom mowed extremely tough sod with a clay loam soil. The trees were set back a year as they struggled for water- very little rainfall penetrated the fabric.

Coarser mulch like wood chips, nuggets and straw actually aids tremendously in allowing even sudden downpours to be absorbed by the soil. The honeycomb affect of worm activity seems a big factor in this regard. During drought it is often the violent and sudden dump of water created by thunderstorms that saves us.


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RE: Best mulches for orchards

  • Posted by mrclint z10SoCal Valley (My Page) on
    Sun, Jan 19, 14 at 10:59

Anti-mulchers, can you point me to some anti-mulching data? I've tried a number of searches on the subject and all I get are pro-mulch recommendations. I don't want to totally rule out that you may be on to something just because it flies in the face of common knowledge, but it would be helpful to see some data.


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RE: Best mulches for orchards

  • Posted by olpea zone 6 KS (My Page) on
    Sun, Jan 19, 14 at 11:51

" How many years have your oldest trees been under mulch, Olpea?"

I believe I started using mulch in 2006, so admittedly not too many years (planted my first fruit tree here in 2002). Still I have mulched very heavily and for the first few years used grass clippings as well as wood chips. I used to be a mulch fanatic and gathered grass clippings a truckload at a time from the city. I knew the trash days for different areas, so I could gather a couple truckloads/week. The woodchip mulch has always been free, so I put it on very thick. Because of my heavy mulching, I would think there might be some "catch up" factor. In other words, in the last 8 years, I've probably put 50% more mulch than what most people would use.

Hman, Fruitnut, and Glib are correct that our summers are hotter and drier than the east. It's also true our soils are more calciferous. But the soil here is also very fertile to begin with. You might say I started with "corn soil" since we grow it here naturally.

I can't say how fruits would react to mulching in the East, but so far I like the benefits of mulch.

I would agree with Clint, wood mulch doesn't add that much N compared to synthetic fertilizer. I think the increased vigor from wood chips results from increased bioactivity, soil aeration, micronutrient balance, and water retention.

One of the complaints of industrialized food is that it doesn't contain the nutrients of home grown counterparts. How much this is true, I don't know, but do know if the soil nutrients aren't there, they can't be available for the fruits. Mulch replenishes the nutrients harvested from the soil.

I agree too much N or too much water can dilute fruit flavor (or make it even inedible). I've experienced it. However, a rich organic soil here makes for large leaves, which (through photosynthesis) combined with all the micronutrients, pack the fruits with flavor, at least as far as I can tell.

I feel like my taste analysis is somewhat objective (as far as tastes go). When I first started growing, I wasn't very discerning about taste, because it was all better than the grocer. I think I get more discerning as the years go by. I can taste subtleties I never used to recognize.


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RE: Best mulches for orchards

  • Posted by fruitnut z7b-8a,4500ft SW TX (My Page) on
    Sun, Jan 19, 14 at 13:13

Mrclint:

No one is saying mulch isn't good for your situation. But you need to realize that your situation is strongly tilted by nature towards high quality fruit: lots of light and heat combined with nitrogen poor soil and lack of water. All you have to do to get great fruit is not screw it up. Others, especially in humid climates aren't so lucky. In many cases the later group couldn't grow fruit outdoors like yours or mine no matter what they do.

99% of those pushing mulch know little or nothing about growing high quality fruit. That includes most large scale commercial growers who think only in terms of shipping quality, size, looks, and yield.


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Good Fruit Magazine did an article on wood chip mulch for apple orchards a year or two ago. In it it was explained that N fixing bacteria become part of the process and eventually substantially increases N supply and vigor of the trees in general- they were talking of a period o8-10 years before this became an issue. T

They suggested it led to the need of more pruning of trees but didn't reduce yield. No mention of affect on quality of fruit was mentioned and I doubt brix was measured in comparison. I tried to find the research on the internet, but came up empty.

Organic matter is the primarily source of naturally provided N in soils, and also increases water holding capacity. How could an ever increasing amount of organic matter not at some point become a liability in a region that averages 3-4" precip a month during the growing season? How could it not?

The primary time of release of this N is when the soil is warmest- just when you don't need it for the fruit. The leaves it is serving at this time are pulling most of this energy towards wood, root and leaf.

Mulch has been an essential component of all my horticultural activities for over 45 years. One reason I've owned a pick-up truck for most of that time was to haul mulch around- in general I love the stuff- just maybe a little too much with my own trees at this site.


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Found it. Not exactly as I remembered it, of course, but pretty much endorsing what I've stated.

There has been very little research on this general subject and I spent half an hour finding this.

The thing is, it takes a very long term study to begin to realize the affects of repeated mulch applications. The affects are huge but gradual, some good but some bad, at least for fruit production.

Here is a link that might be useful: mulch in apple production


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  • Posted by mrclint z10SoCal Valley (My Page) on
    Sun, Jan 19, 14 at 15:03

Hi FN and HM, I know where you guys fall on this subject, and I understand your points. Would you be so kind as to provide a link or search criteria to locate a wider sampling of data? Thanks!


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  • Posted by glib 5.5 (My Page) on
    Sun, Jan 19, 14 at 17:03

One foot of wood chips is quite normal over a decade. If this is a 10 ft tall, vase shape tree, mulched to the drip line, we are talking one ton of organic matter. Wood chips may have a reputation for little N, but the finished humus has about the same N content independent of source, thank to bacteria. I am guessing 10 lbs by the time the chips are composted. One ton of chips will also have 1/4 lb of P and about one lb of K. It really adds up.


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  • Posted by mrclint z10SoCal Valley (My Page) on
    Sun, Jan 19, 14 at 18:09

Thanks HM! I don't see anything there that would talk me out of using mulch. More vigorous trees without increased production would not be a negative for me. I Summer prune to control size, and I thin 10x more fruit than I harvest now. If soil fertility rose wouldn't it make sense for a commercial orchard to simply lower fertilizer rates accordingly?


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It would exceed the needs of the trees even if you didn't fertilize at all. But more important may be the added water retention and other aspects of a soil with so much organic matter it approaches being a muck soil.

Think of how alien to nature this repeated heavy, heavy piling on of organic matter actually is. I used to think OM was so wonderful you couldn't get too much of it, but I have had muck soil as a growing medium and it is good mainly for leafy greens.

However, In the west the ability to control water during most of the growing season eliminates all the negative aspects of "overly rich" soil that I can think of.


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Great thread for us newbie fruit growers. Last year I planted 15 apple varieties on G-11 and G-16. I prepped the the clay soil only by tilling in lime and covered the trees with a couple of inch layer of wood chips and then added 10-10-10 several times during the growing season. The trees took off are are 7 to 8 feet high with nice branching.

I was a happy camper until I realized the trees appear have virtually no fruit buds or spurs. Now I am thinking the growth was way to vigorous and I will probably see very little fruit this coming season. I moved a few of the trees a couple of weeks ago and was amazed at how black and rich the top layer of clay had become due to the wood chips.

With this years planting I will be adding the wood chips but this time, much less fertilizer if the trees are doing well. Chris.


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  • Posted by mrclint z10SoCal Valley (My Page) on
    Sun, Jan 19, 14 at 19:24

There are some gaps in that report. The article doesn't mention fertilizer, does that mean the orchard wasn't fertilized? Two applications of Roundup (or equal) is cheaper than wood chips? What do these other ground covers look like for the back yard grower? Moss covered ground, would that be a good thing?

Chris-7b-GA, 10-10-10 is too much N, as you discovered. I use a 3-12-12 flower and bloom type fertilizer as recommended by DWN.

This post was edited by mrclint on Sun, Jan 19, 14 at 19:25


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RE: Best mulches for orchards

For a commercial grower, roundup is probably much cheaper than woodchips which likely has something to with with the lack of serious research on long term use of mulch as a weed control tactic.

They are expensive to haul and expensive to spread. I know, I haul tons of the stuff every year. In my nursery they are my main weed blocker. Never use herbicide on my property or even on client property. I spread about 30 yards of it on my property last year.

Each nursery tree gets around 1.5 cubic feet of shredded wood. I pay $120 for each 10 yard load I haul from a nearby yard that makes it from arborist chips and brush. Costs twice that to have it delivered but it works better at keeping down weeds than chips and the majority of the expense goes to hauling and application.

When you are growing a couple dozen trees or less, it doesn't seem at all expensive, I suppose.


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  • Posted by fruitnut z7b-8a,4500ft SW TX (My Page) on
    Sun, Jan 19, 14 at 20:45

Chris:

I used to think the same, too much growth on apples during the first years should delay fruiting. But the last two times I planted on G16, M26, and M9 and pushed rapid early growth; I had fruiting the second leaf. Hopefully you'll see the same.


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Yes, I agree, fast growth is the ticket for establishing trees. Worry about excessive vigor later.


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In my backyard I have wood chips all over from the dog who insists on playing in them. He is only one years old, and is 68 pounds. He loves to run at 20MPH or faster and come to a dead stop in them. Needless to say they are all over the yard. When I cut the lawn wood chips are a flying out the mower like crazy! So next year it's only going to be pine straw, which is pretty low in nitrogen, but otherwise does the job. And they hurt less when flying out the mower!
Also the pine straw looks decent, breaths well, and for me are free. Pine straw is working great to protect the strawberries for the winter, and some blackberries are buried under huge piles too. They breath a lot better than shredded leaves, so less chance of moisture damage in the spring.
Anyway considering this discussion, sounds like I should get rid of the wood chips anyway! Actually though I mostly use pine bark, but it is similar.


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RE: Best mulches for orchards

  • Posted by bob_z6 6b/7a SW CT (My Page) on
    Sun, Jan 19, 14 at 22:59

I agree with HM and FN- let 'em rip the first year. I've planted ~10 apple trees per year for the last 3 years, some on the rootstocks you listed, as well as B9, M27, and interstems.

The first year, I really babied things (leaf mulch, topped by wood chips and several applications of fertilizer, with regular watering from drip irrigation) and got good growth across the board.

The 2nd year, I was much more laid back(lazy). I still mulched well with wood-chips and I vaguely recall tossing on a bit of fertilizer once in passing. But I only watered (by hand) a few times during the hottest part of the summer.

In their 2nd year, 80%+ of trees from both plantings flowered. But, most of the ones from the 2nd planting were much smaller. Both dropped a lot of apples, though I think the 1st group did it because of the late frost and the 2nd did it due to their smaller sizes.

In a video I recently linked to in another thread, Terence Robinson (Cornell) emphasizes getting good growth in the first year. He says (and I agree) that it is the key to getting good crops in year 2 and 3. He says it isn't needed, but if you are worried about a lack of fruit buds and want to make sure, just bend a few branches to horizontal and tie them down.


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  • Posted by olpea zone 6 KS (My Page) on
    Sun, Jan 19, 14 at 23:57

I'm still not convinced wood mulch negatively affects flavor. I agree it increases vigor.

It's true wood mulch adds N, but a peach orchard harvests 20,000 lbs. per acre, which is a significant amount of N removed.

A big problem of commercial orchards is the loss of organic matter. It's documented the use of herbicides reduces organic matter. Mulch helps to counteract that.

I may eventually see a reduction in flavor, but with as much mulch as I've put on my backyard orchard, I would have thought I would have seen it by now, if it was going to happen.

As mentioned, I have tried fruits from non-mulched trees around here, and they are no better, and generally not as good.

This summer, I expect the first harvest from the farm orchard (assuming no freeze out). The farm's only been mulched for a couple years and some trees have hardly been mulched at all, so I should be able to do a taste comparison with trees from my backyard.

This would be a more objective taste comparison since I could test the same varieties, under the same management.


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Olpea, it isn't the mulch that is the problem, it is the digested product- humus, which is wondrous stuff, except in excess when you are trying to sustain moderate growth and you are dealing with frequent rain.

Because you don't have so much rain as peaches ripen it may never become a problem, and if it becomes a problem you won't know if it is only the unusually wet season you have when the peaches on some trees seem to be losing sugar. If it happens, see if the older trees aren't the ones most affected.

The only control I have in my observations are the maybe 100 different soil types where I grow fruit. I can compare the flavor of fruit from site to site but this is not a scientific evaluation. I have a site where I grow 15 peach varieties that is a clay loam where most years the peaches are obviously bland compared to other sites where the soil is clearly drier. Other fruit species are not so much affected- plums not at all.

There are studies that show (of apples at least) that excess water reduces the brix of fruit- you can easily find that. Excess N., in itself, doesn't seem to be a problem in this regard.

There are studies that show that OM increases the water holding capacity of soil that trees can easily access (clay holds much more inaccessible water then humus as I recall, although both are colloidal..

If you put this together, the evidence may not be conclusive, but it certainly is compelling. My guess is you've become attached to your heavy mulch technique and you don't want to imagine it could have a bad ending. Because you are raising your trees on mounds and because it is in a less humid area it probably won't. You probably need about 3 more years and a wet summer to even get any "evidence".

Go for the Goldilocks affect- not too much vigor, not too little. An old commercial apple grower wrote an article for Pomona many years ago that stressed that this was the key to the greatest success in managing an orchard. I started as primarily a grower of vegetables where people only worry about too much vigor with tomatoes. I thought soil couldn't be too rich. For most vegetables it almost can't be.


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Thanks guys for the replies, sounds like I am on the right track after all. I have about all the branches on my apple trees planted last winter tied down below horizontal really hoping to produce some apples this coming season, sounds like I will see some fruit this year.

I have to keep telling myself to be patient in getting my new orchard going, glad I'm planted some peaches also, looks like I will have a pretty nice crop on the second leaf. Chris.


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RE: Best mulches for orchards

  • Posted by olpea zone 6 KS (My Page) on
    Mon, Jan 20, 14 at 10:10

Hman,

I agree it's possible flavor issues may yet arise. I also agree water is the main issue and that humus holds more water.

As stated, it may be the drier summers here are the reason I haven't seen problems yet. We do get rain in the summer, like the East, but I think the water demand is significantly greater. Our first peaches start the first week in July. By that time lots of 100 degree days are possible, if not normal. We also get more wind here, which would also increase demand.

The soil/humus does stay moist for a while, but by the time harvest starts, it's dry. If we get light rains, the rain won't penetrate the layer of mulch, further drying out the soil. By the time Redhaven starts to harvest 3rd or 4th week in July, the ground is bone dry (in a normal year) even under the mulch and has big cracks.

I suspect a different dynamic in the East.

If at some point I conclude mulch is reducing flavor, I'll gladly give it up. I don't do much hand spreading at the farm, but pay a neighbor to spread it w/ his skid steer. It's expensive compared to herbicides.


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RE: Best mulches for orchards

"By the time Redhaven starts to harvest 3rd or 4th week in July, the ground is bone dry (in a normal year) even under the mulch and has big cracks.

I suspect a different dynamic in the East. "

That sounds exactly what it is like here. Huge cracks in the ground. Here, it doesn't matter how much it rains in the spring, sometimes a lot, sometimes not much, by July the ground is bone dry.I'm not in the east, but the Midwest, which by rainfall amount is very dry, some states drier than Texas.
Ave rainfall
Minnesota 27.3
Kansas 28.9
Texas 28.9
Wisconsin 32.6
Michigan 32.8
Illinois 39.2
New York 41.8
Connecticut 50.3

Note my rainfall is closer to Kansas than NY. The Northern Midwest does not get the rain the Northeast does. The southern Midwest is more like the Northeast.


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RE: Best mulches for orchards

I also get the bone-dry soil by August most years. I find mulch very handy to keep from having to water in that period. Since I don't water and I fertilize very little and my soil is usually very dry when the fruit is ripening I don't see how the mulch is going to cause a problem with fruit quality. With more fertilizer or more water it could be more of a problem. When I dig up 10-year mulched beds I only see 3-4" of organic soil on top, not sure why it is not deeper. But this makes me think most of the soil the roots are in is still just regular soil.

With or without mulch weeds are a huge problem. I can't just let the grass grow since I am in the 'burbs where that is frowned on. For years I pulled weeds which took countless hours; last year I got a new yard guy and he used roundup but killed too many things. I'm thinking of buying a big flamer this year and trying that method. I use the weed fabric in the blackberries, it works well there. But don't mulch on top of it, that will cause weeds to grow on top.

Scott


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RE: Best mulches for orchards

Yeah I take the first two weeks of August off every year, and come back to a bunch of dead plants. Even when i have people watching it, as water is required daily at that point. The trees are fine, but the smaller bushes, and vegetables look terrible if not dead.


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RE: Best mulches for orchards

My issue with wood mulch is that the #*$&#($* Rose Chafers were laying all their grubs in it! I think the moist/shaded conditions must be perfect... its to the point that if i use a wood mulch, i'm going to have to spray it with a grub killer in summer.


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RE: Best mulches for orchards

If you can spray round up around the base of a trees, how old should the tree be, or is this just an 'overall' bad idea? thanks


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RE: Best mulches for orchards

MrsG47

The bark on young trees needs to be protected from overspray. And make sure no roots are exposed.

Older trees with undamaged bark should be safe.

Mike


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RE: Best mulches for orchards

  • Posted by olpea zone 6 KS (My Page) on
    Mon, Jan 20, 14 at 16:36

"Kansas 28.9 [inches of rain]"

Drew,

The part of Kansas I'm in actually gets about 10 more inches/year (about 38").

Kansas is slightly unusual in that there are vastly different climates in the state. In western Kansas, it's very dry like a desert. They even have tumble weeds. Western Kansas is in the rain shadow of the rocky mountains, so precipitation is minimal. As you move east in the state annual precip increases.

Our funky weather is part of the reason peaches die here if not in a raised planting. Our springs are soppy wet, which kills the fine root hairs of peaches (in our soil). Then it gets hot and dry. The ground dries out at a time when the tree's water demand is the highest. The tree has no fine root hairs to scavenge what little water is available in the soil.


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RE: Where does the mulch go?

  • Posted by olpea zone 6 KS (My Page) on
    Mon, Jan 20, 14 at 16:46

" When I dig up 10-year mulched beds I only see 3-4" of organic soil on top, not sure why it is not deeper."

Scott,

I remember reading somewhere, something like 25% of the mulch by weight, actually becomes soil. The rest releases carbon back into the air. And since its by weight (and mulch is "fluffier" than soil anyway) it takes a long time to build a lot of soil with mulch.

As I recall, an acre foot of topsoil weighs 3 mil. pounds. So to build, say, 6" of topsoil on an acre, it would take 6 million pounds of wood chips (1.5 mil X 4). More mulch than I'd ever want to shovel in my lifetime.


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RE: Best mulches for orchards

Do you have voles? Not moles, voles, a kind of mouse-like, semi-underground (and majorly UNDER MULCH, particularly landscape fabric with mulch over it) little beast common in the notheast that adores chewing on plant roots and bark, with devastating effect durng the winter when the mulch and snow protect them from the cold.

Trees like to have mulch over their roots, but I would keep grassed areas in the space between the rows to avoid providing voles with any un-needed habitat. You don't have to have golf-course-like short turf, just mow it down from time to time during the season. Maybe three to fives per year, depending on when you are trying to interrupt a pest cycle. I use a European-style scythe, which is quiet and lays the grass down where I can easily add it to the mulched area. Very soothing work.

Not all chopped-up wood and bark is good for mulching fruit trees. Some is very competitive for soil nitrogen, and some types create conditions that are actually harmful (as they decompose) to needed soil micro-organisms. You want to try and get ramial wood, not simply chopped up big trunks and branches. If it comes in bags, it's probably not so good (besides being absurdly expensive). But even the stuff that comes from power companies' chippers might have issues depending on the source and its proximity to particulate-emitting pollution.

How about seeding between the rows with a succession of annual cover crops, that are periodically cut down and left in place to enrich the soil or just raked over to the tree root zone in prepartion for seeding another cover crop in the aisles.

The things is that if you want pretty lawn between your trees, you pretty much have to do lawn-type mowing. If you prefer, or can put with, a more meadow-y look, then you can experirment with beneficial cover crops, pollinator flowers (choose those which only bloom when your trees are not in bloom to keep pollinators focused on your trees' blossoms), or just a mowed field look.

However, a large, open area of bark mulch is not a natural phenomenon, because in nature a woodsy duff covering the soil only happens under the drip and shade line of the trees. When you create an unnatural ground cover, you are setting yourself up ffor more work and more problems, sometimes both.


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RE: Best mulches for orchards

Beside the thoughts on mulch, I am curious to hear other people's experience with various layers under the mulch. I have tried newspaper, cardboard, old sheets and landscape fabric. All have their advantages and disadvantages. But I've come to the conclusion that there is no perfect underlayment for mulch.

Landscape fabric is great if you intent to keep a manicured bed, and aren't adding too much organic matter on top. After several years of adding lots of mulch in my orchard, the soil has rebuilt over the fabric, and it no longer prevents weeds (which are now coming in from above the fabric). At this point it is too hard to remove the fabric and the only choice seems to be add another layer.

Newspaper/cardboard and the like work fine for a couple of years and then they breakdown and the weeds can get through. Although they have the advantage of not requiring removal when they stop working.

My limited experiments are pointing me towards using decomposing layers under the mulch and just accepting the fact that I'll be doing it all again in a few years.

I'd be curious if anyone has had a different experience.


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RE: Best mulches for orchards

Liro, most of the problems you suggest about mulch don't often apply to fruit trees in my experience. Mulch on top of the soil doesn't decompose fast or evenly enough to cause N deficiencies in most soils according to research I've seen and my own experience. You need to incorporate it into the soil to get this affect.

If your soil I so deficient in N that the mulch takes it over the edge, their are a wide range of N sources to alleviate the issue. By the second season the mulch will probably be adding as much N as it removes as dying bacteria release soluble N. My guess is by the third, mulch will become a source rather than a sink- that is the created humus will more than compensate for fresh added mulch.

As far as ever being a problem as they decompose to soil organisms- research on that would be appreciated. I've never seen any visible evidence of anything like this happening where it showed up on the growth of the trees.

Ramial wood is mulch made from small branches- its' advantage and disadvantage, I believe, is higher mineral content and a higher N to C ratio than mulch made from larger wood. It can be highly stimulative to growth for this reason- even in the first year. I used to seek it out, especially when lots of green leaves are in the shredded mix. Power companies can sometimes be a source for free.

I agree that the vole issue is very real and a strong reason listed in the old books for avoiding the use of mulch in orchards. Voles are especially a problem next to seldom mowed sods where people are going for an orchard in a meadow look. Extra care must be taken to keep them under control and the standard advice is to pull the mulch from the trunks in fall. That may not be adequate and trapping, baiting and/or trunk wrapping may be needed.

When I use fabric I either lift it every year or every other year before mulching. Newspaper helps with some weeds and works well in the northeast, although I've heard in drier climates it can harden up and repel water. I've also used cardboard.

Shredded wood works as well as woodchips over newspaper or even landscape fabric in my own site as a weed stopper. There are some weeds, such as field bindweed to which this doesn't apply.


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RE: Best mulches for orchards

i use woodchips and leaves. both cheap and easy to get. i am wanting to use straw. i also have an army of ground covers. each one providing nutrients to the soil. leaves tend to have nutrients like iron and what not which isnt the easiest to put into the soil. i find grass a pain.


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RE: Best mulches for orchards

Franktank, What harm do rose chafers do? Do they affect fruit?
What do they look like? Norhwoodswis


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