Fish Explorer Logo
Colorado Fishing
Colorado Fishing  
Login Usr:Psd:
Don't have an account? Register now...
spacer spacer
Go back to Main FxR Forum listings
Lake: Crown Hill Lake

What is the benefit of killing the weed beds?

Post By: fishinbeech      Posted: 6/4/2018 4:05:11 AM     Points: 604    
This lake is nearby so I've fished it plenty. For the 3rd year in a row a crew has been sent to apply weed control. They spray the hemlock around the shoreline. Fair enough. Those plants grow tall and block the view. Apparently, there is also something applied in the water which kills the weed beds. I haven't personally witnessed this but was told, (the first year they did this), that a crew member was in the water applying some weed control. I believe it because the weed beds that used to dominate this lake have not been present since. This has ruined the bass fishing during the heat of the summer. Not only that but since they've applied the stuff this year the bass fishing has abruptly changed from very good to very poor. Up until the day the crew was there, we were catching fish. We haven't caught a single bass since. I've done ok going after other species but zero bass. Does anyone know why they do this?
 Reply by: i2fly      Posted: 6/4/2018 8:13:51 AM     Points: 2100
It's better question for Jefferson county open space. 303 271 5925. Maybe they can shed some light on your question. Good luck!
 Reply by: 007      Posted: 6/4/2018 8:39:52 AM     Points: 81
This should be followed up on with Jeffco and CPW. Substances which kill aquatic macrophytes and algae can be toxic to aquatic life and should not be applied without public notification and a clearly defined goal as part of a lake management plan. Aquatic plants provide critical habitat for fish, invertebrates and are a part of the base of the food chain. That being said, an overabundance of aquatic plants and algae can cause or contribute to poor water quality (usually once they die and decompose) and can paradoxically lead to poor conditions for fish growth and survival. Applying chemical plant/algae control usually takes place in lakes that recieve a lot of runoff from areas with lots of nearby fertilizer applicaiton (think ponds within urban developments/golf courses) and which have no or limited fishing. I would strongly suggested reaching out to the Jefferson County Natural Resource people as well as CCing a CPW biologist or water quality coordinator.

The Jeffco Natural Resources Specialist is Chelsea Beebe at , Paul Winkle is the CPW biologist for the area: his email is and Melynda May is the CPW water quality coordinator at Please reach out to these folks and let us know what you hear from them
 Reply by: fishinbeech      Posted: 6/4/2018 4:12:17 PM     Points: 604
I will do that, thank you for the info! The crews did post some signage in several conspicuous spots to notify visitors that an herbicide had been applied. The signs were dated and provided the name of the herbicide and a generic statement like "weed control". That's about it. I'll report back. Thanks Again!
 Reply by: panfishin      Posted: 6/4/2018 9:11:12 PM     Points: 9002
I remember that they did something last or that at Prospect Park ponds in wheat ridge a few years ago, killed off a bunch of the main weed beds in Tabor and West lakes. I think I had heard back then that the city had gotten a lot of complaints (from non fisherman obviously) that the weeds werenít aesthetically pleasing to those who were visiting the park and walking along by the trails. Not sure if thatís the real reason that they did it or not but that was the rumor that I heard at the really only changed how I had to fish those ponds and not the overall success rates once I realized that I didnít have the same old weed edges to rely on every trip, I actually learned more about the lakes when that happened because it forced me to try different things and more areas to get my bites once the fish had dispersed from their normal and comfortable haunts of the thick weed beds.

Keep fishing there but try out some different areas and look at things a little differently (look for differences in bottom content, steeper drop offs, and isolated rocks or weed patches...they should all hold fish at different times of the day). Find where the forage went to after the weeds died and you will find your fish again. It will take a few trips to figure out the new lay of the lake but it will be worth it
 Reply by: bron      Posted: 6/4/2018 9:18:25 PM     Points: 43914
Well done Panfishen.
 Reply by: rkhancock      Posted: 6/4/2018 11:48:32 PM     Points: 22834
I've heard about them killing weedbeds with pellets out in California. Fished a tournament on Clear Lake in northern California two weeks ago and I heard multiple people talking about this. Also saw tons of dead fish. Not sure if the two are correlated.
 Reply by: frydaddy      Posted: 8/16/2018 10:34:54 PM     Points: 1098
I don't do any bass fishing but have you caught any saugeyes or perch in this lake?
 Reply by: fishinbeech      Posted: 8/18/2018 3:22:55 AM     Points: 604
Here's a long overdue update on the weed killing inquiry:

I've exchanged a couple emails with Paul Winkle but nothing pertaining specifically to the weeds. He said Jeffco holds the reigns on managing the lake so they should have the answers., that is the ball behind me, clearly in my court, with a thick layer of dust on it and maybe a cobweb or two. This might be a good time to confess that I can procrastinate with the best of 'em. I could try and blame it on the dang dog for eating my computer, but, if he was still around he'd be about 26-years-old now. I'll get on this directly.

As far as trying different approaches/strategies/terrain, etc. I have done this and will continue searching. I've had a little success early in the day but no breakthroughs, that's for sure. We've also focused more of our attention on the saugeye and met with limited success. Mostly, we were just lucky enough to be there twice this year, on evenings when the saugeye were unusually aggressive. Total coincidence.

One other thing I should make clear is that I've seen no evidence that any harm has come to the fish as a result of the weed killer. In fact, based on the bass I was catching routinely back in late spring/early summer, The only conclusion I can draw is that the average bass has gotten larger
Operation Game Thief
Call to report illegal fishing/hunting:
Email CPW