How quickly did the area around Mount St. Helens recover, show signs of new growth, after the eruption?

I'm in Portland Oregon and we were covered in ash from Mt St Helens when it blew. The newscasters doing 24/7 coverage, when looking for something new to say, found somebody that explained the ash was going to be good for our gardens. I think they were just trying to help us feel better about all the required repeats of washing down our cars, sidewalks, streets, and indoor floors as it got tracked in, and the daily morning ritual of having to open the hood of the car and put a fresh toilet paper cover around the air filter.

As you might guess, then we had all the arm chair experts, you know the type, gardeners that have never planted a garden but know it all, telling us over and over what wonderful magic was going to happen in our gardens. One quickly learns to just smile and nod, as any talk of facts upset them greatly and caused much screeching. ;)

As far as how the garden improved... I'm still waiting. Thirty three years so far.

This post was edited by plaidbird on Sun, Apr 14, 13 at 12:29

Of course, your soil to start with is probably volcanic and maybe recent enough geologically to not have had most of the goodies leached out, so a fresh dusting of ash didn't make a noticeable difference in crop performance. Bring it out east to leached soils especially south of the glacial zone and might be a different result.

If we could have huffed and puffed and blown some your direction, without the Rockies getting in the way, I'm sure if we had thought of it, we could have gotten a big turn out for the event. What a mess we had. It was only about an inch or so deep at my place, but it lasted for a very long time.

Thanks for adding to the story, I could have done a better job of telling the tale.I agree, it was just adding more of the same to our soil. We have one volcano, Mt. Tabor, right here in the city itself, an easy walk from my front door. Plus Mt. Hood ( also a volcano) is about an hour/hour and a half away. It's the one you see when they do a photo of Portland to promote tourism. We see it everyday when outside, and you would see it on our postcards.

But now that we're here, I have been wondering about the huge landslide business they are doing now, selling types of rock dust to all my neighbors. Since all rocks are not the same, I've looked up the two most popular.

Glacial Rock Dust
Ingredients: Derived from glacial moraines located in British Columbia, Canada.
http://www.planetnatural.com/site/glacial-rock-dust.html

and
Cascade Minerals-Basalt
http://cascademineralsnw.com/product_facts.html
doesn't really say what it is from what I can see.
This ??? "Buffers both high and low pH levels in soils"

I realize without soil sample results this is all just theory, but I'm not sure adding these is not more of the same, same as MT. St. Helens ? I may be missing something here.

This post was edited by plaidbird on Sun, Apr 14, 13 at 20:07

Oh-oh..spoke before I double checked. Seems the Rockies were not in the way as much as I thought. Amazing.

Here is a link that might be useful: check out where the ash did drift.

This post was edited by plaidbird on Sun, Apr 14, 13 at 20:01

I have been close enough to mt hood to see it in reality, as it happens. I reckon without ancient/historical volcanoes we'd have all starved to death by now, but I can imagine that being around real-time eruptions is no fun at all.

Also I would think you must be correct that volcanic soils as recent as in your region would not much need rock dust additions.

I often hope it's not just me being older and set in my ways, ya know ? I read here over the years in hopes of keeping up with what might be new. So thank you very much. Boy, adding rock dust is just what they all do now. It's not just the hippy dippy's either.( not that there's anything wrong with being a hippy dippy )

I'm glad you have been able to visit Mt Hood. It's such a beautiful place. One we do take for granted too often. It's a place where we grew up going on the weekends, and continue through the years.

Now after Mt St Helens ( which still looks broken to me) , I have brief moments when I consider Mt Tabor.. if it were to blow, I'm pretty sure I'm a toastedbird. I'm older and slower now, and one of those people that always says " no..you first". Probably wouldn't make it out from the middle of the city in a mass exodus. Hope my garden comes back impressively though.

Thanks again.

This post was edited by plaidbird on Mon, Apr 15, 13 at 0:12

Bearing in mind that what I have said is guesswork on my part.

I remember a thread where someone (maybe even me) looked up the composition of that red pumice but I can't find it now.

One thing about your question - is that pumice rock sold as mulch any good besides as mulch? - unless it's ground to powder, it doesn't release any of its minerals very fast. So, unless you have a way to crush it, it's not going to do much.

If you can make and use compost, it's going to have (by definition) all the minerals used by plants. Unless you just don't have enough, or your soil is VERY poor, you should be OK with compost. JMHO, from the land of rich clay soil. :-]

" use compost, it's going to have (by definition) all the minerals used by plants."

Variations on this theme are very frequently stated as fact. I keep asking, without getting any good answer, why would that always be true, and how would we know?

There's nothing magic about volcanic rock. If well ground it can be useful as a mineral additive to soil, just like about any other natural rock deposit. There are a number of solid additives for sale that originate from powdered volcanic rock, and like most ground natural mineral additives the availability of the mineral content will be affected most largely by soil pH. Typically the dominant base of volcanic rock is silica ( same as sand).

A number of "famed" agricultural soils are known for their high volcanic mineral content, including Idaho, HI, Italy, northern CA, etc. But in those areas the essential requirements for good soil remains the same, and volcanic mineral content via well degraded deposits (think millennia) doesn't change what constitutes good soil.

Mt. St. Helens is not a useful basis for comparison, at least not in our lifetime. That was a dump of volcanic ash on top of everything, not incorporated into the soil. It's more comparable to dumping a load of very dirty sand on top of whatever was growing.

This post was edited by TXEB on Mon, Apr 15, 13 at 18:53

I have read that old volcanic soils can be quite nutrient poor, like old soils in general. Other than glaciation, volcanoes are the primary way that fresh minerals important to plant growth are brought near enough the surface to be broken down over a few millennia by weather and mitigate the problem of ancient soils, as I understand it.

"If you can make and use compost, it's going to have (by definition) all the minerals used by plants."

Not necessarily. I can make great compost from shredded paper and horse manure, with nothing else added. Does that, by definition, have all the minerals needed in the proper ratios for tomatoes, or peppers, or Brussels sprouts, or carrots, or ...? The minerals supplied by compost will depend upon from what the compost is built, and the amounts supplied will depend upon the rate of incorporation. The real trick with compost is the formulation, not just that it is compost.

Not to mention whether or not all horse manure, or even paper, has the same mineral composition.

I was at an indoor garden show this past weekend and one of the vendors was advertising this product.

Here is a link that might be useful: Volcanic Minerals Plus

The old volcanos & the volcanic rock strew all over many places in New Mexico is in arid areas & doesn't seem to have been broken down much over the years in this dry, hot climate so may not have contributed much to soil fertility as it would in say, Hawaii. We have both the dark & the red volcanic rocks & not sure if there differ in fertility/composition? In the garden here I don't see much of an improvement around the rocks & the red 'scoria' crushed rock used in some older landscapes makes a stained mess when broken down!

Thanks for the replies. I bought a bag of the red rock form (not crushed) lava rock to add to potting mix for house plants. I never used the whole bag. I heard about tomatoes that tasted better in Volcanic soil. It was a post on this forum. I have crushed the rocks with a hammer, which is easily done, I add it to raised beds for veggies, potting mix, when I spread shredded leaves under trees. My in ground soil has good texture but showed a need for Phos and Calcium BADLY, I got Gypsum and Bone meal. The others are in the below optimum column, but not by much. I am glad to know it is okay to use, even if it isn't SUPER GREAT for my soil, It will do no harm if I use a dusting on top of shredded leaves or done compost.

Unless you actually add minerals to your compost, it won't have any minerals in it. It will, however, have whatever chemical components of minerals were converted into living tissue.

If you want to get an idea for the mineral composition of your volcanic rock, look at this chart. It's called Bowen's Reaction Series, and it is a guideline to how minerals crystallize as magma or lava cools. The rule of thumb is that very dark igneous rocks (volcanic and plutonic) will chart in the upper two sections; if you have a very dark igneous rock, it is probably a basalt or a gabbro because ultramafics are rare in the crust. Dark-grey to medium-grey rocks chart in the intermediate area, while pink/red, light-grey, and white rocks chart in the felsic area.

As mentioned a couple of times above, however, coarse pieces of these rocks are not going to break down quickly enough to have any significant nutritional benefit for your garden. They would have to be either pulverized or sourced from ash deposits.

weirdflowers - interesting! Where does obsidian (perlite) fit in?

Even though it's black, obsidian is chemically felsic. It technically does not contain minerals though, because of the amorphous arrangement of particles within it (it cools too quickly for crystals to form). There are other forms of volcanic glass though; for example, when basaltic lava is extruded at mid-ocean ridges, it forms pillow-shaped rocks covered in a glassy crust.

Fascinating.

Our very old volcanos on the west side of Albuquerque don't seem to support any greater growth of plants nor do other types of volcanic rocks in other areas of the State but guess because of the age, dry climate & type of volcanic rocks they don't break down as readily as those in Hawaii do & support plant growth readily & so soon after eruption. Not sure what the NM types are but know there is obsidian (? "apache tears') & the red 'gravel' type used in landscaping years back.

"Unless you actually add minerals to your compost, it won't have any minerals in it. It will, however, have whatever chemical components of minerals were converted into living tissue."

WF, I've been puzzling this statement over for a while. Can you expand further on what you mean by it?

I think when we talk about adding "minerals" to soil or compost we are generally not talking about pure elements, because these rarely exist in a form that we would normally be able to source, even if it were desirable to add them in pure form. So for example, when we talk about putting "potassium" in the soil, perhaps in the form of wood-ash, we are not adding pure elemental K but rather potassium hydroxide and maybe other compounds based on K. Various forms of K exist in soil, though I don't know in what forms, and trees and other plants assimilate those compounds. My understanding is that most if not all minerals useful to plants - if they are extant in the soil - exist in complex forms synthesized by soil microbes. The wider the range of useful macro and micro nutrients that have been "digested" by microbes from more elemental forms, the more fertile the soil for plants.

This generally explains why sandier soils are more impoverished than silty and clayey ones, am I right? Where the parent material happened to have a dominant quartz component the commonest particle size ends up no smaller than a quartz molecule, which is very large, and so many of the compounds based on trace elements slip through the profile over millennia leaving an impoverished and droughty landscape.

I believe I understand the mineral point - it is the exact speciation or combination of elemental constituents that constitute a "mineral" in the true geological and chemical sense, e.g., calcium carbonate, kaolinite, etc. They have a balanced chemical composition, and are naturally occurring. There are over 4,000 specific naturally occurring geological minerals.

In agriculture or nutrition when the term "mineral" is used it is applied more loosely, generally referring to the chemical elements that are essential for a living organism, excepting carbon, nitrogen, oxygen and hydrogen, without regard for the chemical balance or the balanced composition of their occurrence in soil or the organism. Hence we talk about calcium or phosphorous or sulfur or iron or copper as minerals, without regard to how they exist in a balanced compound or salt. Mostly the term is applied to the metals, but it also includes several familiar nonmetals (sulfur, phosphorous, chlorine, iodine, and selenium). Chemically, a more proper term than minerals would be "elements", recognizing that they generally don't occur either in diets are ag applications in their pure elemental form.

TXEB just about nailed it. There's a couple of other points as well: the chemical components are arranged in a crystal lattice, and the chemical composition can vary but only over a defined range.

Very sandy soils are generally nutrient-poor because even though "sand" describes the size of the particles rather than the mineral components, sands usually are relatively enriched in quartz, whether quartz was a dominant component of the parent rock or not. Quartz is both very hard and, unlike most minerals found in igneous and metamorphic rocks, is extremely stable at surface conditions. So when a rock is weathered and sediments are carried downstream, non-quartz minerals will break up into very tiny grains more easily than quartz, and will chemically weather to clay minerals (which are also soft and easier to break into tinier grains). That's a good enough generalization, though in reality you can occasionally find sands that have very little quartz content in them.

weirdflowers - guess you don't accept the amorphous ones as "minerals" (e.g., obsidian, opal, etc.). Must be a crystallographer at heart.

You're right, those ones are mineraloids ;)

I enjoy mineralogy petrology, but I'm not a crystallographer. Actually, I'm halfway through a BS in geology :)

This post was edited by weirdflowers on Wed, Apr 17, 13 at 13:32

I knew as soon as I suggested that homemade compost would provide minerals, someone would challenge it. Yes, I agree manure and paper would probably not have the mineral content of yard and kitchen waste compost. It was meant to be a general statement.

I agree that w/o soil testing, you can't know for sure. On the other hand, there is also no evidence that one needs volcanic rock minerals either.

I maintain that for the casual gardener, in the absence of actual data showing a deficiency, compost will pretty much take care of your needs. It worked for grampa.

I was questioning the assertion that compost will always provide every nutrient a plant could use, not that compost has nutrients.

Yeah, I get that. I think we're on the same page with this. :-]

As far as my compost goes, I add gypsum, bone meal, Blood meal, Alaska fish fert 5-1-1, Bunny poo tea, very strong bunny poo solids with water, in other words. Egg shells in powder form, shredded leaves, sawdust, veggie scraps and coffee grounds. The compost should be fairly high in some nutrients. I will be starting a new raised bed pretty soon. The Yew shrubs that have been there for 30 + years are getting removed. I will be making a raised bed for shade loving perennials there.

poaky1 - gypsum, bone meal and egg shells are all high calcium materials. Depending on amounts you incorporate into the compost, the amount of compost you use, and the soil type and pH in which it is used, you could you could be headed for high calcium levels. It's something worth watching for over time.

I have never had too much Calcium problem on soil test, so I get what you're saying, but I don't think I need to worry for a while. My phosphorous is very low on soil test, I am hoping the bone meal will help with that. The gypsum is of course calcium, my PH is 6.0, I have lots of acid lovers, so avoid lime.

volcanic rock dust is loaded with what most gardeners and farmers need....healthy soil, healthy plants, healthy people...end of health problems in our country.....it is costly to apply, but your soil builds up so not necessary to keep adding every year....i have noticed my tomatoes need way less water...once a week, or twice if hot weather....let your food be your medicine, plus a little sunshine...i use azomite...can find online about a dollar a pound delivered...alisorganics.com...try out, use 1/2 cup per plant at planting time...the indian

It's unfortunate that this excellent thread was adulterated by a spam post, but also fortunate in bringing it back to view.

So thanks, indian! Maybe a few more people can read the thread and learn a little from the well-educated participants.

"The end of health problems in our country." Haha!

Here is a link that might be useful: When a product claims to solve all your problems

TXEB- in the SW high Calcium may stay like that for a long while. In my Climate high calcium won't stay that way long, unless there is a limestone deposit a few ft down. Pa does have limestone deposits, but I had a dificiency in calcium in my veggie garden before, so I needed to add some to the soil. My Tomatoes get Blossom end rot every year. It effects the first bunch of ripening tomatoes most. It is said to be from low calcium levels. That is my main reason for adding all that calcium.

Even here in NM we often times find some tomatoes w/blossom end rot. I use Epsom salts around those plants & it works too.... & cheap!

The fact that Epsom salts works on BER is an indication that it is not directly related to calcium, since Epsom is magnesium sulfate. I get BER on the first few tomatoes and peppers, then it goes away. I have not tried to preempt it with mag sulfate, just never seem to get around tuit. :-]

There are many benefits to using volcanic rock dust powder. The first of which is providing slow, natural release of elements and trace minerals. The key is to get it in a dust/powder. If the rock is to large it may not absorb naturally. Check this out: VRP Solution

But soil is already full of minerals in a dust/powder form.

The original post is questioning the nutrient value of volcanic rock and mentions that they should test their soil; suggesting that they are concerned that nutrients and/or minerals helpful in plant growth may be missing. I just wanted to share that if soil is lacking in nutrients, volcanic rock powder is definitely the way to go. Check Soil Depletion for detailed test results.

And by some miraculous coincidence, CanAmaze just happens to sell volcanic rock supplements ... so no wonder he/she thinks they are fabulous.

I have yet to see the Blossom end rot, my tomatoes need a few more days til they get ripe, I am hoping my compost helped., I put it down last fall.

I have yet to see the Blossom end rot, my tomatoes need a few more days til they get ripe, I am hoping my compost helped., I put it down last fall.

The major benefit of Volcanic Rock is to the people that sell it.

There are many nutrients in volcanic rock dusts that will be released for plants to use when the soil microbes, the Soil Food Web, releases them and that means the soil this volcanic rock is applied to needs adequate levels of organic matter to support that Soil Food Web. As many studies have found soils well endowed with organic matter have ample supplies of nutrients plants need to grow strong and healthy.

kimmq is kimmsr

I can't help but think the red pumice rock is super rich in some kind of very beneficial trace elements because in the areas around my house that I laid it down as landscape rock weeds grow into in the Spring and I have never seen anything so prolific in my life. There is wild geranium full of pink blossoms that grow like crazy on this. I also have large sword ferns growing around it and it thrives and grows way better than any other location in my yard with the same soil. I have to believe there is something in there with a powerful nutrient growth effect. I'm doing an experiment pulverizing some of it and putting it around my tomatoes to see what happens. Crossing my fingers!

If only the plants we TRY to grow would grow as well as the WEEDS. Then we'd really be getting somewhere.

Edit: I was just looking at another thread about eucalyptus wood and apparently it's very high in manganese. Too bad you can't find some eucalyptus wood chips to mulch with!

Here are a couple of links to the composition of red pumice, aka scoria.

https://www.researchgate.net/figure/Chemical-composition-of-scoria-samples-Scoria_tbl2_236147186

https://www.researchgate.net/figure/Elemental-composition-and-oxide-content-of-red-scoria-and-pumice_tbl1_319048806

Neither of these really focuses on trace elements, so there isn't a complete inventory of what we would consider plant-relevant elements. But in general, even the ones in higher concentrations are less than 1% (some even less than 0.1% according to the second link). What I get out of this is that a dusting of this stuff is not going to do anything that an occasional amending with compost can't do.