View Full Version : Weed growth?

01-02-2010, 07:49
weed growth, what makes the weed in our lakes bad one year and not so the next? :confused:
does it grow in cycles etc..
any ifo appreciated, thanks


01-02-2010, 09:29
Always thought it grows in cycles of 7 or 8 years but I suppose there must be more to it than that. Reading university were very helpful to me on this subject some years ago and produced a number of scientific paper reports which I'm sure they published on the net somewhere.


01-02-2010, 09:32
Do cold winters have any great effect on the following years weed growth?
I always suspected it was a popular misconception that cold winters 'knocked it back'.

Mr T
01-02-2010, 12:31
Do cold winters have any great effect on the following years weed growth?
I always suspected it was a popular misconception that cold winters 'knocked it back'.

We can still have a cold winter and lots of sunshine, which from my experience can encourage the weed to grow, especially in crystal clear cold water.

01-02-2010, 12:59
Must have somthing to do with the nutrients too, a mega weedy year must take a lot of the goodness out of the silt etc

01-02-2010, 13:00
So many variables... birdlife, water clarity, various nutrient levels, temp, natural cycles, natural springs, acidity levels make some nutrients more and less available etc. etc. no one-size-fits all answer

We've had a cold winter, lots of ice cover to shade out sunlight; yet some lakes are still chocka with weed, others are barren....

01-02-2010, 14:11
The text books state canadian pondweed grows on a 7 year cycle... I've never actually seen it stick to it mind!

All things are relative, so don't expect a water choked with weed to be completely clear! A water which receives lots of sunlight and is high in nutrients (phosphates, nitrates etc) is going to encourage the weed is going to grow.

My theory is that the weed (with canadian anyway) seems to grow from the root bed into thicker and thicker beds, as it does so it rises higher and higher to compete for more light, cutting off light to weed below. Eventually you get the floating weed masses that break away and die off. The weedbed is still there and will start again in a season or so.

Changes in the environment and the amount of available light and nutrients can make a huge difference, for example: If the water is normally coloured with algae and this dies off, the weed can suddenly get more light and a boost of nutrients and away you go.

Tight lines


01-02-2010, 18:06
cheers for the imput so far fellas!
Guess ill just have to wait and see what happens, as id imagine it will differ from one lake to the next!!

01-02-2010, 18:10
I thought that with the harsh weather we've had, the lake being frozen and then with snow on top creating constant darkness for a couple of weeks it would've killed off a fair bit of weed.

HOWEVER in my lake the weed is still there and still quite green! Although the growth seems to have died back a bit this year.

I'm hoping the 7yr cycle is in full process and we're well into the cycle, thus less and less over the next couple of years. It won't all go, but it won't be like a football pitch!

01-02-2010, 18:36
HOWEVER in my lake the weed is still there and still quite green! Although the growth seems to have died back a bit this year.

Brought in some bright green silkweed on a couple of deadbaits at the weekend plus there was some bright green Canadian washed up in the edge - seems to be growing well despite the cold.

Another football pitch season in prospect on this water by the looks of things

01-02-2010, 19:39
one of my lakes i fish is weedy wasnt that weedy to start with 10yrs ago. but over the years the more bait that goes in the weedier it gets like fertlizer!!

02-02-2010, 13:10
The cold will only slow it down, by slowing the chemical processes (photosynthesis etc) - but not stop them, as soon as it starts to get lighter (it already has!), the weed will respond by growing.

It will be interesting to see what the hard winter has done to algae growth - as if this isn't present in the water column then you will get more light penetration, equalling more rapid weed growth.

02-02-2010, 13:59
I tend to think that a cold winter will aid for better weed growth the following year :norty: :norty:

Theory behind that is, if the previous years weed growth dies back to the extent that the actual lake bed is exposed and no dieing/dead weed is left to block & mask the sunlight from the actual lake bed where the roots are housed, if there is a load of dead/dieing crap on top it takes a lot longer to penetrate the base of the weed thus it will not reach it's full growth potential

I know nothing about weed to be fair, gave it up a while back, so for arguments sake it's a 7 year cycle, 5 more years and I'll be blazing it again. :D

02-02-2010, 14:55
good answer Hitchy, i was waiting for someone to come up with a reply hinting towards the other form of weed lol.

02-02-2010, 16:08
roll on the those 5 years

02-02-2010, 16:32

02-02-2010, 19:52
With regards to the annoying weed, do you think that there is a depth that it grows from? Just that i found 2 years ago, we would get the weed growth with water upto a certain depth, and past that it was clear.

If you are able to get good photo's from google or bing, it does show up the shallower areas.

03-02-2010, 07:11
yes mate id agree with that! could be wrong but id put that down to photosynthesis ie.. the deeper the water the less light can penetrate and get to the bottom