the urine of an organism
dirt
Mold
yello paint
A dull mower blade will "tear" the grass instead of "cut" it. The jagged blades of grass will dry up and cause your lawn to look brownish or even yellowish - much like when cut grass clippings turn from green to brown/yellow as they dry up.
Because the soil is dry and you need to add water
If a black sheet of plastic is laid on the grass, the grass will turn yellow because the the starch produced in the grass gets consumed up . since no sunlight is available to the plant to produce more starch,it will gradually start turning yellow. ;-) ---------------------- The loss of green coloration equals the loss of chlorophylls, which is the result of the plant putting chlorophylls in storage when sun light is absent.
Most likely it's the end of the peas' growing season in which they will turn yellow and die off.
That is the grass dying. Plants need sunlight in order to photosynthesize. Covering grass with a board is depriving it of sunlight.
Some varieties of tomato have yellow fruits and therefore this is perfectly normal.
Other than by painting it yellow, all you have to do is cover it up, and the green chlorophyll pigment will fade. Grass under temporary swimming pools usually turns yellow and may begin to ferment (rot). Grass that stores its pigment during the winter usually turns brown (tan) rather than yellow.
its red in color
Well, there are different answers to that question, this is one of them. When dogs do their business in the same spot over and over again a patch of dry, yellow grass can form.