With the lack of rain in recent months I have noticed water levels dropping and large areas of weeds/pads dying.

I was wondering what causes the weeds to die? I would think more exposure to sunlight would cause the weeds to grow in more and further out into the lake where the depth prevented them from rooting. If plants need water and sunlight to thrive, seems like as long as there was water there more sun would only help. Obviously this isnt the case.

A local lake has lost about 70% of its hydrilla. The remaining patches are brown and look unhealthy. This isnt too big a deal since the lake is deep and there was a LOT of hydrilla to begin with but another smaller local lake has lost a lot of pads and the remaining ones are browning and dying off. This was a super hot spot for topwater every night but recently I am lucky to get 4 fish and nothing above 2lbs.

Seems like the O2 level in the lake is dropping and killing the plants. Why?

Too hot of water could be killing the plants. I would say that the O2 levels is dropping because of the plant decay.

Im curious about this as well. I posted almost the same post a while ago and it was moved (for some unknown reason) to fishing reports....lol. Never got a clear answer...Im guessing its mostly to do with oxygen levels.

the o2 levels would affect aquatic life but plants dont use o2, rather sunlight via photosynthesis. (one thing i remember from biology class!!) They in turn, create oxygen. At least this is how I usnderstand it, might be different for water plants.

Also, in shallow lakes I can see how the water could heat up but the lake I mentioned is a deep reservoir although with little water movement it makes sense that the weeds along the banks are dying.

Excessive heat will kill some plants, maybe when the water temp gets to a certain level, the hydrilla cant handle it....

thanks for the replies. might have to do some googling to find out more.

Plants do use O2 at night time though instead of Co2.