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Tree’s causing soil acidity

Is there an online reference that lists what trees cause soil acidity, and to what degree they cause it?

The search function didn’t turn anything up, and Google didn’t help either.

Thanks in advance.


LawnSite Senior Member
Anytime a nitrogen fertilizer is applied the soil becomes a little more acidic. It has to do with the hydrogen ions and atoms and amounts thereof in the soil. Other contributing factors are the parent rocks and growth of plants that uptake nitrogen, manganese, sulphur etc. and are then removed that cause acidity. There is the process of allelopathy in which certain trees and shrubs create toxins that reduce the abilities of other plants to grow in the same area. Juglans nigra is the one most people recognize. It produces a chemical called juglone that prevents other trees from photosynthesizing sunlight. That's why it's so bloody difficult to grow anything around black walnuts or butternut trees. Alianthus altissima is the other famous example. Back to your original question, trees can cause acidity do to the uptake of nutrients, and decomposition of root hairs. To what degree, well that's a chemistry lesson that is.