Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Where is my FA coming from?

I am seeing more and more FA on the bottom and on structure. When I bought the 0.6 acre pond 4 years ago I didn't see any and at that time the pond was estimated to be 9 years old. The only changes I made to the pond were adding fish (no fish prior to my ownership) and cutting down the wall of willows that surrounded the pond.

1. Although the pond is solely fed by runoff, there are absolutely no agricultural chemicals or livestock waste in the runoff. The pond is on top of a hill and the closest ag activity (grain crops) is at the base of the hill. The watershed is covered by unmowed weeds and brush.

2. I have never fertilized the pond.

3. I don't feed the fish. The pond 'operates' naturally. No human intervention other than a few treatments of glyphosate to knock down any new willow growth.

I really don't understand the increase in FA unless the fish themselves are providing the nutrients. I don't have the floating mats yet but I won't be surprised to see them in a couple of summers at the rate the stuff is growing.

Any ideas about what is going on? Thanks guys!

Comish, I have no idea what is going on but you're not alone. There have been years when a bunch of us reported the same thing. I've always suspected fish adding to nutrient overload during low water times but you're not in the drought belt like I am.

A "No Trespassing" sign, backed by pellets, didn't do much good for my duck problem. Those darn things made a real mess out of one of my one acre water holes. Then hogs made a greasy, algae ridden mess out of a couple of small forage ponds.

Comish,Seems like the longer we go through winter without snow cover the more spirogyra algae we see.It thrives in cold clear water in midwest ponds. It seems to run in cycles as I believe it is sunlight related. Even when we test phosphate (PO4)as P and get a reading of <0.01 mg/l ,very very low we still see spirogyra as it requires very little P. I also see it in ponds where it has not been a problem in the past once amurs >grass carp< are stocked as the P level goes up as the oxygen producing,nutrient removing plants, "weeds to some" are eliminated. Another example is when chara is controled a lot of the times it is replaced by FA.As spirogyra fades out in the summer it is often replaced by lyngbya or other look alike FA's.

Add me to the list of people with a new FA overrun. My pond is not new but this FA problem sure is. Started in the Fall, seems to have increased in quantity/coverage over the winter. I am very afraid of what mess is lying under my ice. Sad times.

What readily available treatment can be used to get rid of it? Normally I try not to use any chemicals in the pond and haven't to date, but this is out of hand. Biggest problem I will have is finding a source for the chemicals here. Thanks.

Pottsy what is the alkalinity of your pond and its size ?

We have lot's FA this year as well, last years chara has died off and the FA has taken it's place. The chara die off started early last year with an extremely stong cold front with high winds that super cooled the water column on just the windy side of our pond, this also created a cold water algea bloom in march last year. I think the other part of this has been the very mild weather we had in the fall. When I was ice fishing last month I pulled out out LMB that had some FA stuck to it's top fin.

I haven't tested the alkalinity for a while... I have been lax. But... last time I did I saw 180PPM with a PH of 8.1

Pond is about 1 1/4 surface acres.

That is to high [base] to use lime around the edges. So that trick won't work. Do you have a plankton bloom yet?

No significant bloom as of yet. I used to have between 10-16" visibility... it went to 2-4+ feet at the same time the FA showed up. Probably sucked thr nutrients out of the water.

That big increase in visibility let the light get to the FA and it started growing. If you can cut off the light penetration the FA on the bottom (> 3 ft)will die back.

Besides increased water-clarity, removing the "wall of willows" from around the pond probably opened the door for more sunlight-penetration into perimeter shallows - which is FA's preferred habitat.

FA is the new bain of my existance... I was really hoping it would die back over winter but so far it isn't looking like it. My fear now is if I have to fertilize to get the bloom back. (Which I never had to do before), that I will be feeding the FA and not making progress. The other bit of fun will be trying to remove as much live/dead FA as I can given it is so horribly plentiful. ARGH!

Pottsy, you think you have a mess, secchi disc readings last fall were 120" plus at our pond.

Woah! That is like the really nice looking spring fed cold water ponds up here. Nice to look at, swim in and for trout but not much for production.

Actually, it's full of aquatic weeds which take up most of the nutrients and keep the water clear, we have milfoil, coontail, sago and chara. LMB densities have been over 200 fish per acre.

Lets see Shorty -- 4oz X 200 LMB = 800oz divided by 16oz per pound = 50 lbs of LMB per acre. That is just about right. :p

All kidding aside you need to get some of them out unless it operates like a Fla. phosphate pit at a ton+ per acre of fish biomass. That is unless they were counting in July and included a bunch of yoy in the count.

Ewest, it was a late fall count for a fisheries class at UNL back in the mid 90's, based on the low recapture rates they estimated the LMB population at 205 LMB per acre with lots' of 6" LMB. We did remove 20-25 lbs. of LMB per acre last year with no noticable decrease in the catch rate until August of last summer, even though the majority of the LMB were removed by mid June. We took out 240 LMB in the 10" to 16-3/4" range and of those half of them were 14-1/2" or better.

You should see all of the 1" or less BG in the pond right now, I must have seen 2000-3000 of them last Sunday in and along the flooded grass, and those are just the ones I actually saw. It would not suprise me if there are 10 times that many in there right now.

Did I mention that we do have high phosphate levels in the pond? :p

Shorty when they did the study did they provide what they thought was the fish biomass per acre ?
I have seen underwater films of those Fla phosphate pits and you can barely see the water for all the fish. It made me dizzy watching from all the schools of fish darting around and the predators going wild. The fisheries scientists estimated the fish biomass at 2500 to 3000 lbs per acre.

Sorry ewest, no estimate on the lbs. per acre, but there are always lots of small BG everywhere you go when out in the boat and the weeds create an ernomous amout of structure for the fish.

Ah, so not as deep as I assumed. I was thinking gravel-pit pond.

Brother Pond Owner,
I am seeing this issue for the first time. Never cared before. Now I have a newly dug pond and kids that were duck in their last life. FA is on a roll as far down as 6 feet, maybe deeper. Isn't this too early?
Jones fish hatchery suggested Cutrine Plus? Is it safe and how does it work, I don't know. I never wanted to resort to chemicals, but the battle rages.
Thanks

ewest, whats the link to the FA control page?

I wish there was one. There are a # of threads here but no one size fits all answer. Start with understanding the basics of light excess nutrients and water -- mix them and you have weeds. This link may help a little. But as Bill says " it all depends" on the situation in your pond and every pond is different.

http://aquaplant.tamu.edu/database/algae/filamentous_algae_mgmt.htm