Just want to ask this question from the community.
Hoping to get a good answer.
Sandy soil can be high in alkaline where I am because of lime stone.
Lime stone is very high in alkaline and contains many calcium nutrients for many coastal variety of plants.
Many plants that need clay soil will not grow well with sandy lime stone soil.
But in other countries not where I am in Australia.. can sandy soil also be neutral or not high in alkaline?
I don't know if that is true or not that's why I am asking this question. Hope we can discuss this?
Do all sandy soil have lime stone or does some sandy soil just a sedimentary rock base without lime?

Sandy soils have acidic pH and the clay soils are very alkaline. My clay soil ranges from 7.4 to 8.2. Sandy soils are rarely alkaline, however there are a few exceptions to this rule.

I couldn't agree more with Luke on this topic!

I must very strongly disagree.

Sand or clay is a grain size of material. Whether it is alkaline or acid depends on the climate and rock the original material came from. If your sandy soil came from limestone, yes it will be alkaline. I live in the desert and because of the climate ALL of our soil (sandy and clay rich) is alkaline. Because our original rock is granite, if the climate were lush and green we would likely have an acid soil with a nice forest on top. (Exactly like the rainy side of our mountain range over in California.)

I never thought about the active climate effect on soil too much, but have always thought soil types - whether clay or sand - depended on their source and therefore could be either one or the other. Climate effect makes sense since in that a warm, wet climate, organic material is constantly being added and would effect it. Particle size is what distinguishes the ranges of soil texture though and that would reflect the acidity and alkalinity of the source from which it came.

needrain said:
Particle size is what distinguishes the ranges of soil texture though and that would reflect the acidity and alkalinity of the source from which it came.

The source material in Nevada and California is granite (with a lot of other stuff but no limestone). If you took granite and ground it into dirt, it would have a neutral pH and be nutrient poor (but there are some salts released). On the east side of the Sierra Nevada mountains, the Great Basin desert spreads out for 1000 miles. No rain and thousands of years of compounding salts from the granite so, the soil is alkaline.

On the west side of the Sierra Nevada mountains, it rains and snows and there are trees and plants. As those plants die and turn into humus, the soil becomes more acidic and nutrient rich. Same base with different results due to climate.

If you go back far enough, Giant Sequoia trees grew our part of the desert and there was a giant inland lake (fresh water) in Nevada and Utah. But, at the end of the ice age, 10,000 years ago, the climate changed, the inland lakes dried up and the desert was born.

When it rains the rain filters carbon dioxide gas's in the atmosphere and forms carbonic acid in the water. When water meets with the acid the result is a more hydrogen ions added to the water which will drop the pH. Areas with a high amounts of rainfall have more acidic soils because of the carbonic acid added to the soil. Rainfall has a lot of influence on the soil when you are looking at over all soil pH outdoors.

Our sandy soil is slightly acid. This is an area with plenty of rain, and the soil is an ancient sandbar.

Areas of high pollution, particulate matter in the air, that get rainfall end up with acid rainfall. The classic example where I am from is the adirondacks in New York State. They are down wind from Michigan, Ohio, etc. and when that air was carried eastward towards the Adirondacks, rainfall through the pollution produced the acid rainfall.
The Amazon Rainforest has more inches of rainfall then possibly anywhere else in the Western Hemisphere and they might have acid water also. But I think it may be from the vegetation. It has to do with the tanin in the water. Oak forests have more tanin the a maple based forest because oak leaves have tannin
So it is not the amount of rainfall but what it falls through or on that changes acidity. I am sure the leaves in the rainforest have different levels of tannin the cause changes in acidity.
On Long Island we had poor air quality lots of time due to industries west of the city. In Florida, the air quality was better because there is very little in the way of significant industry west of Fort Myers. There is the Gulf of Mexico and Mexico.

I'm in a segment of the Carolina sandhills... There's also Nebraska sandhills... and... lets not forget white sands New Mexico.

In my area... the sand is acidic. the clay is acidic.
https://www.nrcs.usda.gov/wps/...

https://www.nrcs.usda.gov/Inte...
The Piedmont soils of northern Crawford and Taylor Counties formed from the weathering of parent material from biotite gneiss, a rock type of the Carolina series.Consistent with this rock type are alternating beds of schist and quartzite. TheCretaceous deposits of the Coastal Plain extend southward from the Fall Line,thickening at the rate of approximately 35 feet per mile.
The Tuscaloosa Formation, which is the most extensive formation in the survey area, rests on the underlying crystalline bedrock and covers most of the area immediately south of the Fall Line. This formation consists of white sand and sand mingled with kaolin and lenses of kaolin.

Out in New mexico where the sands are formed of gypsum... the internet says they are slightly alkaline... 7.8 ph

The Nebraska sandhills are Calcareous ... and considered alkaline... 7.0 ph

Sooo...
Seems to indicate that the ph level is at least partly predicated on the material that the sand is formed from.

Many different sandstone exists on different parts of the world.
But if it's true that not all sandy soils have lime stone then different stones can exist that contain different ph levels and nutrients for plants which can alter ph levels.

I definitely believe that not all sandy soils are high in alkaline but further research needs to be done to find out why? In Australia we have a lot of limestone and dolomite stone. Dolomite is high in magnesium and it's great for cell devision in plants.
We study the main nutrient source and then trace elements.
According to what I read from you guys... yes sandy soil is different on many different places in the world. I don't think any sandy soil would be acidic unless organic matter is added.

Aussie, I believe you are correct. Daisey is right up to a point, but between the Sierras and the coast there are valleys and other small mountain ranges...some of which were under the sea back in the day. I worked in landscape in the LA basin, which is a watershed. My area was a former streambed. We could dig in with our hands for a bit, then the sand turned to clay you couldn't break with an auger... all within 10 ft. What comes down from the mountains affects the ph of what came from the sea, where only the strong survive.

Its all about particle size: boulders, cobbles, gravel, sand, dust... the chemical makeup is the same. Your sand used to be bigger but will eventually be dust and maybe clay. My sand turns into hardpan. Particle size.

Carol, you ran into hardpan. Its what happens in CA and Nevada but, in California, its worse. Have you ever heard of blasting to plant trees? They started dynamiting to plant trees in the Central Valley in the 1800's. They were still doing it in the 1950's, at least on a small scale. That's how our trees in Sacramento were planted.

But, its still the same problem: Particle size.

... yes sandy soil is different on many different places in the world. I don't think any sandy soil would be acidic unless organic matter is added.

Convince me that all minerals or elements that can make up sand are always neutral or alkaline....
-- -- -- only then will I believe you.

Leftwood said:... yes sandy soil is different on many different places in the world. I don't think any sandy soil would be acidic unless organic matter is added.

Convince me that all minerals or elements that can make up sand are always neutral or alkaline....
-- -- -- only then will I believe you.

Well.... if you mix in the sandy soil to improve it and add organic matter for example my vegetable garden is sprouting very well as I added soil media into the sand mix with pea straw which will only make it slightly more acidic but not very acidic.
Because of traces of dolomite stone and lime stone in our soil will make it very alkaline but calcium bicarbonate will make it slightly lower enabling a more balanced PH hydrogen peroxide levels.

ctcarol said:Aussie, I believe you are correct. Daisey is right up to a point, but between the Sierras and the coast there are valleys and other small mountain ranges...some of which were under the sea back in the day. I worked in landscape in the LA basin, which is a watershed. My area was a former streambed. We could dig in with our hands for a bit, then the sand turned to clay you couldn't break with an auger... all within 10 ft. What comes down from the mountains affects the ph of what came from the sea, where only the strong survive.

I think I am correct. Thank you.
Lime is not in every country on earth.
Because there are different minerals that make up different soil.
About sandy soil turning into clay soil that is rather interesting and very geological.
That can also happen in certain parts of melbourne in Australia.

limestone
Dolomite stone.

Dolomite is another sandy soil base mineral rock.
Same as lime stone.
Both have almost the same chemical affects in soil.
But they have different properties of minerals as limestone does not have magnesium dolomite does!

and... there's the great sand dunes in Colorado....
https://www.rockngem.com/color...

Leftwood said:Convince me that all minerals or elements that can make up sand are always neutral or alkaline....
-- -- -- only then will I believe you.

Sigh.... Lordfungi, in your answer, you restated unrelated facts and experience. My statement was meant to be rhetorical, as I assumed everyone would know that the actual mineral and element pHs are unchangeable without external influence.

lordfungii said:I don't think any sandy soil would be acidic unless organic matter is added.

Show me then, how a sand derived from an acidic parent mineral is never acidic. I want to learn, and I am happy to say that I am wrong if I am. Please show me.

A hydroxyl group is a functional group that attaches to some molecules containing an oxygen and hydrogen atom, bonded together. Also spelled hydroxy, this functional group provides important functions to both alcohols and carboxylic acids. Hydroxy is the determining factor when it comes to stabilizing the pH. What lordfungii said about lime stone is correct in that the pH is governed by hydroxyl and not hydrogen ions.