Well, yes...it's summer. Surface waters are hot! Got a call from a loyal Pond Boss magazine subscriber and forum frequenter who lives in central Missouri.
He'd searched the forum, looking for a specific answer to his question, then found my number and called.
He has a pond there in Missouri, slightly smaller than two acres. Based on recommendations from his nearby fish hatchery, he added ten cedar trees about 15 feet tall. He told me he has an olive-colored plankton bloom, visibility about 18". His question, "My hatchery guy is planning to stock yellow perch next fall and told me to add another 5-10 cedar trees, but I'm concerned whether to do it or not right now with my bloom like it is."
Other facts, he's got bluegill on the cusp of two pounds and is culling largemouth bass.
Should he add more cedar trees right now, early August?
No, he shouldn't. If those ten trees he's just placed, full green, have even 100 pounds of needles each, then he's just added at least 1,000 pounds of "hot" organic matter. Those needles will start falling off with a week at these temperatures. His pond will do what it does, especially in this heat. As the cedar needles begin to decompose, they'll give off byproducts in the form of gases, which can be toxic to fish at some level. As that process continues, nutrients will be released into the water, further fertilizing his bloom. Cedar needles have lots of nitrogen, with some phosphorus.
My advice was to hold off until November, when water temperatures drop into the 50's, then add the remaining trees. I also recommended he add some artificial structures such as Mossback Fish Attractors, or some rock piles, hardwoods with no leaves, concrete block piles, tires bundled with holes drilled in them.
His mission is to raise big bluegill, diversify his fishery, and add habitat for young fish.
Right now, your water is working hard to grow things, process wastes, and manage what's dissolved or suspended in it.
Watch your water, it will tell you volumes.