Pond Boss Forums GENERAL QUESTIONS Water chemistry Forest fire effects on water chemistry?

A large part of my Watershed that supplies water to my pond burnt last November. It was a hillside containing mostly Oak and hickory trees and the fire mostly just burnt leaves and underbrush. What effects might this have on my water chemistry?

There will be little to no Nitrogen or amino acids in the ash run off. What you will see is high potassium and calcium numbers. Really nothing to worry about.

The elements that are in the ash will be very fine and water soluble and available for life to use. Many tribes believed fire was a blessing and a new beginning increasing the growth in that area.

Cheers Don.

I agree with Don. The chemicals that come in the pond are far better than any leaves that might have been washed in.

My only real concern might be silt from the unprotected watershed. Could some sort of cover crop be planted under the trees?

You could plant a thick swath of annual rye grass above the pond to catch silt. That would work to catch silt until leaf cover re-establishes this fall and winter. Next spring shade loving weeds will grow under the trees until the brush re-sprouts from roots. The rye will be effective until about June.

Agree with the group and it could actually help (potash - fire remains) is often a missing or low element in pond water.

"Since wood ash is derived from plant material, it contains most of the 13 essential nutrients the soil must supply for plant growth," said Sullivan. "When wood burns, nitrogen and sulfur are lost as gases, and calcium, potassium, magnesium and trace element compounds remain. The carbonates and oxides remaining after wood burning are valuable liming agents, raising pH, thereby helping to neutralize acid soils."

Silt won't be a problem. There is 500 yards of grown up pasture between the hill side and the pond. Iv been wondering if it had something to do with the high pH. The pond was started last year and was finished this spring.my pH is down from 8.8 to 8.0 now but all the other ponds in my area are more in the 6.8 range.

IMO, As with most anything, ash is good but anything in excess is probably not so good. I add one bucket to my compost pile from the fireplace. More than that and the plants in the garden don't do so well with weird shaped leaves and stunted growth.