Grass in shade

[Freckles]

I have three oak trees and I cannot get grass to grow under them. I know St Augustine will grow in the shade, but can anyone recommend a grass that will grow from seeds in a shaded area?

Thanks

[beecrofter]

look into shade tolerant ground covers

[brooklyn1]

You have more than a shade issue. Oak trees turn the soil beneath extremely acetic, making it very difficult if not impossible to grow lawn grass successfully. Sometimes liming with shallow tilling can help but usually not, and can more likely damage your trees. I don't know where you're located so I can't give you detailed recommendations, perhaps you can get more help by accessing:

[gardengal]

with soil acidity. Plants do not make soil acidic - acid soils occur as a result of the mineral content and amount of rainfall. As Victoria notes, much of Texas has chalky, limestone based soils and relatively low rainfall, ergo many Texas soils are more alkaline than acidic.

Large trees like oaks do not encourage much in the way of undergrowth and certainly not lawns. This is because they have large, expansive root systems that outcompete smaller plants for both moisture and nutrients. And you don't EVER want to till in the root zone of an established tree - that is a recipe for disaster! Look for a dry shade tolerant groundcover for this area. Anything will need some help getting established by means of regular watering intitially and possibly some supplemental fertilization. But you will fight a losing battle trying to get any kind of lawn to thrive in this area.

[Billy]

In article , gardengal wrote:

AAAAAAAAAAh - wrong

All nitrogen is not the same

Ultimately, from the plant's perspective anyhow, the role of the soil food web is to cycle down nutrients until they become temporarily immobilized in the bodies of bacteria and fungi and then mineralized. The most important of these nutrients is nitrogen?the basic building block of amino acids and, therefore, life. The biomass of fungi and bacteria (that is, the total amount of each in the soil) determines, for the most part, the amount of nitrogen that is readily available for plant use.

It wasn't until the 1980s that soil scientists could accurately measure the amount of bacteria and fungi in soils. Dr. Elaine Ingham at Oregon State University along with others started publishing research that showed the ratio of these two organisms in various types of soil. In general, the least disturbed soils (those that supported old growth timber) had far more fungi than bacteria, while disturbed soils (rototilled soil, for example) had far more bacteria than fungi. These and later studies show that agricultural soils have a fungal to bacterial biomass (F:B ratio) of 1:1 or less, while forest soils have ten times or more fungi than bacteria.

Ingham and some of her graduate students at OSU also noticed a correla- tion between plants and their preference for soils that were fungally dominated versus those that were bacterially dominated or neutral. Since the path from bacterial to fungal domination in soils follows the general course of plant succession, it became easy to predict what type of soil particular plants preferred by noting where they came from. In general, perennials, trees, and shrubs prefer fungally dominated soils, while annuals, grasses, and vegetables prefer soils dominated by bacteria.

One implication of these findings, for the gardener, has to do with the nitrogen in bacteria and fungi. Remember, this is what the soil food web means to a plant: when these organisms are eaten, some of the nitrogen is retained by the eater, but much of it is released as waste in the form of plant-available ammonium (NH^). Depending on the soil environment, this can either remain as ammonium or be converted into nitrate (NO,) by special bacteria. When does this conversion occur? When ammonium is released in soils that are dominated by bacteria. This is because such soils generally have an alkaline pH (thanks to bacterial bioslime), which encourages the nitrogen-fixing bacteria to thrive. The acids produced by fungi, as they begin to dominate, lower the pH and greatly reduce the amount of these bacteria. In fungally dominated soils, much of the nitrogen remains in ammonium form. Ah, here is the rub: chemical fertilizers provide plants with nitrogen, but most do so in the form of nitrates (NO,,). An understanding of the soil food web makes it clear, however, that plants that prefer fungally dominated soils ultimately won't flourish on a diet of nitrates. Knowing this can make a great deal of difference in the way you manage your gardens and yard. If you can cause either fungi or bacteria to dominate, or provide an equal mix (and you can ? just how is explained in Part 2) , then plants can get the kind of nitrogen they prefer, without chemicals, and thrive.

p 25 -26

Teaming with Microbes: A Gardener's Guide to the Soil Food Web by Jeff Lowenfels, Wayne Lewis

? Publisher: Timber Press, Incorporated (July 15, 2006) ? ISBN-10: 0881927775 ? ISBN-13: 978-0881927771

[gardengal]

If you had done any serious study of soils aside from only reading what has been written by others, you would know that what I wrote is entirely correct. Plant life and soil microbial content has only a minimal impact on unamended soil pH. Soil pH is dependent primarily on the two factors I stated - the native mineral content of the soil and the amount of rainfall it receives. Areas of high rainfall tend to have acidic soils; arid locations tend towards alkalinity. Plants that grow in acidic soils did not create that situation nor do they make them more so - that's mistaking representation for causation. Plants grow in acidic or alkline soils because that is to their liking. Oak trees don't create acidic soil - they grow in acidic soil because that is their preference. Acidic plant debris on the surface of the soil can create a slightly lower pH on that surface, but it does not penetrate to any significant depth into the soil strata. The amount of organic matter one adds through incorporation - not just lying on the soil surface - to a soil can lower pH but it would take considerable quantities to affect any significant change. That's why it is recommended to add minerals - sulfur or lime - NOT organic matter or other plant life to alter a soil's natural pH.

"The parent material of soils initially influences soil pH. For example, granitic soils are acidic and limestone-based soils are alkaline. However, soil pH can change over time. Soils become acidic through natural processes as well as human activities. Rainfall and irrigation control the pH of most soils. In humid climates, such as the northeastern United States, heavy rainfall percolates through the soil. When it does, it leaches basic ions such as calcium and magnesium and replaces them with acidic ions such as hydrogen and aluminum. In arid regions of the country (less than 20 inches of rain per year), soils tend to become alkaline. Rainfall is not heavy enough to leach basic ions from soils in these areas.

Other natural processes that increase soil acidity include root growth and decay of organic matter by soil microorganisms. Whereas the decay of organic matter gradually will increase acidity, adding sources of organic matter with high pH values (such as some manures and composts) can raise soil pH.

Human activities that increase soil acidity include fertilization with ammonium-containing fertilizers and production of industrial by- products such as sulfur dioxide and nitric acid, which ultimately enter the soil via rainfall. Irrigating with water high in bicarbonates gradually increases soil pH and can lead to alkaline conditions.

In most cases, changes in soil pH, whether natural processes or human activities cause them, occur slowly. This is due to the tremendous buffering capacity (resistance to change in pH) of most mineral soils."

[brooklyn1]

Billy, you are correct. But if one understands the original question ?growing grass under oak trees? the answer is far more simple than your technical discourse.

*With a stand of pine trees (or oak trees), the needles/leaves that they drop are going to have an influence on the soil pH *local* to the trees. It's not the actual plant changing the pH, it is the vegetation decomposing and adding to the soil that can indeed alter soil pH.

Other than light and water there is no other concept more basic to gardening, anyone who doesn't comprehend this does not garden. Anyone who is any kind of gardener knows this instinctively. That's why gardening centers have stacks and stacks of lime (and peat moss) right near the lawn growing products. Anyone who doesn't know this simple fact of local plants altering soil pH has never been to a garden center other than as a spectator sport.

If someone is trying to grow lawn grass under any tree and the grass is struggling the first thing even the most novice gardener does is test the pH of the soil directly below the tree... anyone who has actually done any gardening automatically tests soil pH *prior* to planting anything that hasn't grown there previoauly... the same way one knows to put their socks on before putting on their shoes a gardener checks soil pH under a tree before planting grass, it's part of the soil preparation the same as with planting a vegetable garden, a rose bush, even a corn field, etc., it's just that simple.

I suspect some here do not garden... they only talk gardening... someone else is doing their landscaping, and perhaps they help so they pick up the nomenclature, that they toss around in an attempt to give credibility to their preachings... this is true with any endeaver where someone is quick to say others are wrong but cite no reference other than their own say so, and then cannot reply with the correct answer, but instead hide behind a decoy of nonsensical double talk/fluff speak.

[Billy]

You ain't seen nothin' yet ;O)

Thanks for keeping it simple.

Soooo, basically what you are sayin' is that Jeff Lowenfels and his book are full of crap, not worth buying, and that plant exudates have nothing to do with soil pH. Is that about it?

What may be your credentials be to to impugn Mr. Lownfels, besides dirty finger nails, i.e. what is the basis of your authority, so that we can all be properly impressed?

a really good day ;O)

[Bill]

No Billy is a major pain in the ass. Trying to impart a bit of avant-gardening knowledge is difficult if for no other reason our source for info is media given all other fringe hence the good dialog.

This site is full of useful info but If I go to to Walmart I don't think it would be mentioned.

Has a few videos BTW.

Your text books are your own ? Think about it.

Bill

[Billy]

You are indeed correct, as to the original post, which is why I've started a separate post, "Jeff Lowenfels called out".

Gardengal, with much hubris, claims that only the intrinsic soil components determines the soil pH. For example, most of the U.S. east of the Mississippi was once forest (acidic), in those areas where large scale modern monocultures (injecting ammonia gas) don't exist, according to Gardengal, that those areas should still be acidic because they were once forest areas (historically acidic soil because of fungi).

Now, the above is just an example. The main nut of the thing is do soil organisms change soil pH? I have no expertise in this area, so I must rely on experts. Either Gardengal or Jeff Lowenfels is wrong, or they will come up with a situation that I hadn't considered (which isn't too far fetched). In any event, it should be a learning situation.

As you may remember, Jeff Lowenfels has posted here before and I'm hoping he will respond, and perhaps we can all become a bit more informed.

If anyone else would like to ask for his comment, his email is [e-mail]

[Billy]

---->

[brooklyn1]

Have you considered remedial reading... it may help your comprehension.

We can see how lovely.

You never tested yet you know its pH... yeah, right... are you psychic... everyone has been buying soil testing kits for nothing. You should start a web business, folks can email you their GPS location and you can email back the precise pH to within +/- 1 millimeter. We don't need any stinkin' pH test kits! hehe

Lots of honest folks admit they're newbies.

Oh, wow, you need your gang... I can see her credentials from here...I'm shaking in my boots. Pam's credentials and a token gets you a ride on the MTA! LOL

A job watering shrubs is a professional nothing. Starting gardening at 15 is like starting to train for being a prima ballerina at 15.

Hmm, obviously I hit the nail dead center.

I don't know whether you're an idiot... but I do know you're a braggart and a liar, and mean spirited... you're not a nice person.

[gardengal]

Alright......let me see if I can explain this so everyone understands.

The chemical properties of a soil - its pH - is determined primarily by its mineral content and secondly by the amount of rainfall it receives. This is a well understood fact of soil science. Of course there are other contributors but they tend to be minor players unless......unless.....they have been added to excess. These would include various pollutants, chemical fertilizers, mineral additives and other amendments and yes, soil organisms. However, for soil organisms to measurably alter a soil's natural pH, you would need to add copious amounts of organic matter or organic fertilizers to stimulate them into a feeding frenzy. The amount of organic or inorganic acids they produce in the course of their natural consumption of normal levels of organic matter is just not sufficient to make major swings in pH levels. Most soils also have a natural buffering capacity that resists any significant change in pH, which is why it is very difficult, if not virtually impossible, to permanently and significantly alter a soil's natural chemical compostion unless frequent, repeated amendments are done to effect that change.

To address the topic of this discussion.........the reason many plants are not inclined to grow under the canopy of any large tree has nothing to do with soil pH. The conditions are just as inhospitable in an acidic soil as they are in an alkaline soil. And that's because the tree is higher on the plant pecking order, often casting dense shade, creating dry conditions by preventing or diverting rainfall to reach plants under its canopy and through its dense and very far reaching network of fine feeder roots that suck up all available soil moisture and ready nutrients. Plants that do tend to grow under trees are those that can easily tolerate these conditions.......and lawns/turf grasses are not one of them. Since large established oak trees have a dense canopy as well as a very dense and spreading root system, it should come as no suprise that lawns - even those that are shade 'tolerant' - have a difficult time competing. For a gardener to reach first for the soil pH testing kit when faced with this situation simply indicates a lack of gardening sophistication and an understanding of basic plant morphology.

If one does the research, they'll find there is really nothing to substantiate the concept that normal debris accumulation from existing plants alters soil pH. This is a gardening myth that has been perpetuated by lack of understanding - pine needles or oak leaves, etc. do not make a soil more acidic.There are many pines and oaks (and junipers, etc.) that prefer and thrive in alkaline soils and the shedding of their needles or leaves does not change that preference OR the soil pH. They do leach some weak acids to the soil surface but these dissipate as they percolate down and the pH of the soil any more than an inch or so below the surface will be whatever that soil pH is naturally. And as they decompose, even very acidic plant debris is neutralized and approaches a neutral pH. That's why most compost tests out at around 6.7 to 7.0 pH.

I think it would be more helpful to look this situation through a big picture perspective. Dr. Ingram's research focuses on the microbiology and how it interacts with the soil. And it does have an impact to be sure. But it does not carry the load WRT the chemical compostion of the soil. It is a bit part player that can be stimulated into a larger role but never that of the leading man.

As to my credentials and the need to post cites, I'm not at all sure how relevant that is to the discussion at hand. If one bothers to research recognized, substantiated cites, the information is there for all to see. I do happen to have a degree in horticulture, have various professional certifications, teach part time for MG classes and at the college level, have published on a minor level and have gardened professionally (and personally) for several decades. But of course no one has the ability to substantiate any of this, so take it or leave it.

[Billy]

Hmmm? And here you were jerking my chain because, quote "If you had done any serious study of soils aside from only reading what has been written by others, you would know that what I wrote is entirely correct.", close quote.

So what your saying is, if I had only listened to you, I'd know you were right? Hmmmm.

Seems you didn't do all the original research on your information either. So why you giving me a hard time for doing the same thing? Or is it I represent a threat, because I can read, same as you, and since I've read others, I might know something you don't, thereby diminishing your "glory"? Hmmm.

You gat serious issues girl.

Speakin' of serious, I gat to find my bottle opener. I ain't worth s__t, till I have breakfast.

[gardengal]

Noooooo. What I said that if you had studied the matter yourself - like took a couple of courses or spent time in the field doing research - rather than just regurgitating what you have found in books, you might broaden your perspective. btw, if you look hard enough, you can find something published that will support pretty much any wild claim. It's more a matter of considering the source and evaluating whether that source has any credence. And if the regurgitated information is even presented in context or applicable to the discussion at hand.

So far your arguments - if one can call them that - seem to be focused more on personal attacks rather than providing any credence to your statements. That says volumes. Go ahead and play your childish little games and feel as superior and self-righteous as you like. I'm pretty secure in my position and with myeducation and experience and certainly don't need your validation.

And you don't??

And that explains a lot.

[Billy]

So, as a teacher, you're telling me that unless I take a class, my studies don't count. Doesn't say much for self-actuated learning does it? And my time observing in the garden is just wasted time? Huh? Who would have thought. Interesting pedagogical approach you have there. You must be one of those "No Kid's Behind Left" types.

I've noticed that from reading your posts.

Which is why I wanted to know your bonifides.

Or a teacher who answers the question that they want to answer, rather than the one that was ask.

Say, you're pretty handy with ad hominems and invectives yourself.

Pu-leez, don't let me disturb your reality.

What, that you can't even win an argument with a dissipated drunk?

It's been a lot of fun but let's get back to the question about whether plants can change soil pH, shall we? After all, that's why we are here. Now are we talking bare, scraped land or a constituent area of the biosphere?

You seem amenable (correct me if I'm wrong) to imperceptible changes to the exposed underlying geological strata, let's call it acute vegetation (all of a sudden a lot of plants). How about changes based on chronic vegetation (plants growing in a spot for a long time)? Would you grant me that there are changes that would take place immediately around the plant and it's roots? Would not there be some change due to the mycorrhiza (acidic) or the bacterial exudate (basic) due to their abilities to dissolve different minerals from the geological substrate? If yes, how far would this change occur? How long before it would become significant?

You must be aware of continental drift. Let's say that as the plates drifted apart that one part becomes, oh let's say South Carolina and the other part becomes, say, Senegal, are you going to have the same type of geologically determined plants growing in both places?

I await your professional response.

[brooklyn1]

Billy, these blabber mouth babe's only professional response will consist of some sci fi theory they read in a fercocktah text book somewhere in a far away galaxy, their lily petal soft manicured JAP hands have never touched "dirt".. they've never worked any land except in their dream books... so far in the months I've read posts here I've not even once seen anything the loud mouthed professionals have actually they themselves planted, not a tree, not a shrub, not a blade of grass, not even one friggin' string bean. Should name them the Flowering Flaming Frauds! LOL

They don't have real lawns in Texass... if I don't know anything else, this Noo Yawk Lung Guylander knows to grow grass, and can prove it. I own 107 acres of the most gorgeous Noo Yawk farmland. But I've already been apprised by some on this group that yoose experts don't want to see actual REAL gardening, hurts yer envious little feelings.

I ain't going away, any of yoose lie I'll let yoose know it.

[Charlie]

LMAO!!! This hit me just right, given current circumstance. Thanks fer the hearty, old trout.

Cheers Charlie

[Billy]

You're welcome kid. Just have to know when to giv'em enough line. Actually, I had oatmeal, bran, molasses, cinnamon, milk, and a banana for breakfast with a large glass of water. (sigh)

Still trying to get used to the idea of being an "organic" Nazi. You know, after all those years of being a "peace" Nazi. It gets confusing trying to figure out what kind of Nazi you really are, another time, another place.

Should have been in the garden today but ended up fighting the propaganda war like a good "education" Nazi (F bush and his freakin' "No Child's Behind Left"). Historically, when you put money into education you get good results. Memorizing laundry lists isn't the way to learn. I really like the Montessori system of where the teacher doesn't have to continually traumatize a kid with tests but the teacher to student ratio is such that the teacher knows what the kid knows through interaction with him/her. Kids ain't little adults. They need time to mature before you put demands on them. American secondary students test below European students in the same grade but European students are traumatized by a test that they have to pass when they are 12 years old, that will determine the rest of their lives. In the US, we hit students hard when they go to college, and we have a list of Nobel Prize winners that is second to none.

Humph.

Have a good dinner. I gotta go check the ribs.

[Charlie]

Indeed. One believes and acts passionately in regard to long held beliefs and ideals.... beliefs and ideals which benefit individuals and mankind, and their reward is being labeled a Nazi. T'was ever thus....and so be it.

Ribs?? Dude...it's sunday......change of routine??

Ahhh...I'd have gone to the garden meself, and missed this fun, had it not been for the ***SNOW***. It's friggin' April here in zone 5/4, fer crissake and two nights of hard freeze on the way........phooey

Edumcation...now there is a fine concept and practice, mostly misunderstood by the great unwashed.

Seems funny that gardengal has such little respect for the autodidactic. Al E. says it best, perhaps... creativity is a type of learning process where the teacher and pupil are located in the same individual.

Here's a little slideshow for those whose edumcati Charlie

"My schooling not only failed to teach me what it professed to be teaching, but prevented me from being educated to an extent which infuriates me when I think of all I might have learned at home by myself." -- George Bernard Shaw