|
| Our property is decomposed granite on the whole with pockets of pine trees. If I scoop up the needles and what's under there, will that add acid to other areas of the yard? Thanks! |
Follow-Up Postings:
|
- Posted by greenthumbzdude (My Page) on Wed, Feb 20, 13 at 21:19
| Yes, pine needles add acidity to the soil |
|
| Temporarily, until decomposition is complete, after which the soil pH will return to what it was. I doubt that there is any truly acid soil in So CA. In my experience, a thick pine needles mulch (several inches) takes down the pH for approximately two years in Michigan. Not clear how to relate this info to much drier California. |
|
| A study done by Dr. Abigail Maynard at the New Haven Ag Research Station in New Haven, Conn some years ago found that soils amended with pine needles and Oak leaves did not exhibit significant change in soil pH even after several years of having those items added to the test plots. I have not seen the pH of my soil change with the addition of Oak Leaves or pine needles or peat moss and instead have seen the pH go from 5.7 to 7.2 after adding copious quantities of these items over the years. Some people claim that adding wood chips as mulch to your soil will make it more acidic yet if those same wood chips are burned and the ash is used the pH of the soil will rise because of the CaCo3 in that ash. Tree leaves, dried and crushed,steeped in distilled water for at least 24 hours will test out with a pH in the 3.0 to 4.0 range wih Maple leaves testing more acidic (3.2) than Oak 3.7). As a rule organic matter will not have a significant affect on soil pH. |
|
| Most of the time. I had a low pile of pine needles, which killed the grass underneath, and for a couple of years all that could grow there was sheep sorrel (a plant that tolerates acidity). By now it is back to grass just as before. When the pile became almost completely composted, I used that to germinate beet seeds (which are sensitive to acidity). 0% germination. All this was at my previous place, with sandy soil and pH=5.5 (BTW, the non-germination clued me to the fact that I needed to add wood ash to a spot if I ever wanted to grow beets, and that finally worked). The difference between wood chips (pH=5-5.5) and ash (pH=10.4) is, of course, the carbon. |
|
- Posted by toxcrusadr 5 (My Page) on Thu, Feb 21, 13 at 11:10
| "The difference between wood chips (pH=5-5.5) and ash (pH=10.4) is, of course, the carbon." I guess it could be said that carbon plays a role in the acidity of the wood chips, in the form of organic acids. However, elemental sulfur will also lower pH with no help from carbon. Just a chemist picking nits, I suppose. :-] |
|
- Posted by TheMasterGardener1 5B (My Page) on Thu, Feb 21, 13 at 11:18
| If your soil has above 6% OM the ph does NOT matter one bit..... |
|
| "If your soil has above 6% OM the ph does NOT matter one bit" Not quite true. Lots of organic matter can help buffer your plants against the pH variation, but is not a substitute for correcting the ph. |
|
- Posted by TheMasterGardener1 5B (My Page) on Fri, Feb 22, 13 at 11:36
| It wont correct it. All nutrients will be available even at a ph of 5... This is why 90% of the time soil tests are not needed for the home gardener not looking to save on not using a specific nutrient, being large farms use tons of fertilizer a year the saving makes sense for them. |
|
| Western soils tend to be alkaline (basic), whereas eastern soils tend to be acidic. Also, soil PH is often very resistant to change because it takes much more acid/base amendments than people are often able or willing to do to change it. If you are in a desert region of CA, then you likely have PH in the higher range. Which then would benefit your soil to add acidic amendments. Your not likely to be able to change your PH significantly no matter the amount of pine needles or pete you use. The bottom line though is that plants grow well in a wide range of ph levels. So you probably don't even have to worry about it. I would not even hesitate to use those pine needles as mulch. Kevin |
|
- Posted by gardengal48 PNW zone 8 (My Page) on Fri, Feb 22, 13 at 16:13
| It is best to avoid generalizations :-) Soils can vary radically from one neighborhood to another - even from place to place in the same garden. Glib's post is likely more close to reality than not. Acidic soils result primarily from the amount of rainfall - heavy rainfall areas tend to have acidic soils; more arid areas neutral to alkaline soils - and secondarily to underlying substrate. Plant material has minimal impact. IME, having gardened there myself, SoCal leans towards the alkaline side of the scale :-) In fact, studies done by UCDavis in 2001 indicate an average pH throughout SoCal of 7.8, well on the alkaline side of things. The best way to determine for sure is to test for pH. The presence of pine trees is not necessaily an indication of acidic soil - the needles don't make the soil acidic and some pine species prefer the dryness of that climate as well as its more alkaline soils. The other consideration to keep in mind is irrigation - water sources there tend to be on the alkaline pH side as well so even an increase in soil acidity via amending can be quickly negated by normal irrigation. |
|
| I wasn't sure if I should start my own thread, but this is close enough to the subject already started. I have several Fir and spruce trees from a christmas tree stand that were dumped after the holidays. There are no pines but spruce and the flat needle evergreens which may be Balsam fir, NO Hemlock. Is it the same as what is above, after decomposed the OM from the trees should be slightly acidic? I will be shredding these trees in spring, needles and trunks. |
|
| The concept that the "home gardener" need not test their soil comes directly from those that want to sell you products you probably do not need, the synthetic fertilizer industry. Since there is no way anyone can know what their soils pH is without a good reliable soil test, or if something is needed to correct that pH and how much of what material that is reason enough for a good reliable soil test. Since many places now ban the injudicious applications of Phosphorus, due to high levels of P in our lakes and ponds that are causing toxic algae blooms, and the average homeowner needs a soil test from a soil testing lab (not a home test kit) to legally purchase "fertilizers" that contain P. "scientia potentia est", knowledge is power. |
|
- Posted by TheMasterGardener1 5B (My Page) on Sat, Feb 23, 13 at 13:21
| "It is best to avoid generalizations " Yea really..... "knowledge is power." Tell me about it.... Posted by Masbustelo 5B Illinois (My Page) on Fri, Feb 1, 13 at 12:20 "The master gardener makes a very good point often misunderstood and ignored. In very healthy soils, say 5%om and higher ph is essentially irrelevant. The cat ion exchange capacity is what determines the availability to plants of nutrients. A cation (+) (pron.: /ˈk�t.aɪ.ən/ KAT-eye-ən), from the Greek word κατά (kat�), meaning "down", is an ion with fewer electrons than protons, giving it a positive charge. The positive ions are to simplify things "open to" or hunting for negatively charged particles. In soils the desirable negatively charged particles are the nutrients, these will chemically bond with the cat ions. The higher the organic matter, the higher the cat ion capacity of a soil, and the higher its ability to keep or maintain the nutrients in the root strata. With high organic matter soils pH becomes irrelevant because there is so much nutrient available at basically any pH that the plants will not have any lack of access and availability therein. Organic matter may be very low in plant nutrients, such as peat moss. Or organic matter may be very high in plant nutrients, such as compost and manures. So then determining factors in soil science regarding high organic soils is not pH, but, is there sufficient NPK etc. bonded to the cat ions?" Like I said, ph does not matter.... Good talk though... |
|
| Tell Azaleas and Rhododendrons that have chlorosis when grown in soils with a pH in the 6.5 range that pH does not matter. Tell Blueberry bushes that do not produce well in soils with a pH in the 6.5 range that soil pH does not matter. Organic matter in the soil can help buffer a soils out of range pH but it is still no substitute for correcting that pH. Plants can survivegrowing in soils with a wide range of soil pH but will not be the strong and heatlhy plants we would want if growing in soils outside the range they evolved growing in. |
|
- Posted by desertdance So.CA LowDesert (My Page) on Sun, Feb 24, 13 at 11:08
| Thanks for all the input. I know the soil is alkaline, and most of our plants thrive in it. There are a few plants that I'd like to show off in some areas, so I was wondering if the pine mulch would work. We have 1.4 acres, most of which will be grapes and figs and they thrive in poor, rocky well drained soil. Just wanted a few camellias in some front yard east facing beds. I will definitely mulch them with pine needles and soil. There are a couple Japanese Maples in the beds also that will create dappled shade for the camellias. Nice to know maple leaves add acid too! I'll get the ph tested, even though I know what the answer will be... :-)) Thanks everybody! |
|
- Posted by TheMasterGardener1 5B (My Page) on Sun, Feb 24, 13 at 11:34
| Yea, but the cat ion capacity ...nevermind.... ;) Those native acidic soils can be lower than 5% OM sometimes lower than 2% so yea, soil ph would matter at that point. farms with low levels of OM really have to keep up with ph tests. |
This post was edited by TheMasterGardener1 on Sun, Feb 24, 13 at 12:31
|
| Have you had a soil test done? The UMass one is cheap. Without that we can't really tell you much. If you dump pine needles on already acid soil without much buffring capacity, it can change the pH temporarily. Put that on calcerous soil with enormous buffering capacity and the pH won't budge. |
|
| "It is best to avoid generalizations" Thanks for the reminder, we should always try to be careful not to confuse people with generalization statements. I should have gone on to say that soil ph is related to precipitation amounts and that the eastern US generally has more than the Western US, which influences the patterns of soil ph. And because the west is generally more arid that western soils are in general alkali. But of course there are exceptions such as the moister areas of CA. Nevertheless what I said is a scientific fact even though there are acidic and alkali soils in both regions. And I did say "desert region of CA." Now to chime in on plant growth/organic matter/ph. Sure organic matter can mitigate some of the effects of soil ph by increasing the cation exchange capacity which can help with macro (N, P, K) and micro nutrients (Fe, Cu, Mo, etc). However, soil ph can have a dramatic effect on the availability of micronutrients, even if high in organic matter content. Even if the cation exchange capacity is high, there still won't be anything to exchange because micronutrients are locked into forms not usable by plants because of the ph. Your plants will still grow, but they won't be able to maximize growth unless all limiting factors are adressed, which includes both micro and macro nutrients. |
|
- Posted by gardengal48 PNW zone 8 (My Page) on Mon, Feb 25, 13 at 18:16
| Just to make sure this is perfectly clear - plant material, regardless of acidicity, will not significantly alter the existing soil pH. Any changes it will make will be slight, temporary and occur only at the soil surface or where they come into direct contract with the soil. To alter soil pH to any significant degree you will need to amend the soil with chemical additivies - sulfur (more acidic) or lime (more alkaline) are the most common and widely used for this purpose. And even then there is a limit to the amount of change one can effect and how long it will last. Many soils have a buffering capacity that will return them to their natural status quo. If you need to alter soil pH to any significant degree (more than 1.0-1.5) then it is usually recommended to plant in containers or raised beds where you can more closely and easily tailor and monitor soil conditions. |
Please Note: Only registered members are able to post messages to this forum. If you are a member, please log in. If you aren't yet a member, join now!
Return to the Soil Forum
Instructions
- You must be a registered member and logged in to post messages on our forums.
- Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review the contents and make changes.
- After posting your message, you may need to refresh the forum page in order to see it.
- It is illegal to post copyrighted material without the owner's consent.
- HTML codes are allowed in the message field only.
- No advertising is allowed in any of the forums.
- If you would like to practice posting or uploading photos, please visit our Test forum.
- If you need assistance, please Contact Us and we will be happy to help.