Are leaves in ponds really a problem?

[werdnal]

For several years we had our pond covered in wire netting to prevent our son taking an unintentioned dip. He's 7 now, so last summer we decided he was sensible enough to remove it. From what I remember, last Autumn was a wild and windy spell, and the surrounding trees lost their leaves almost overnight, and they blew away. This year being a more settled, they are falling fast and straight into the pond. We have about half a dozen goldfish, lots of newts and frogs, and many bottom-dwelling invertibrates. The pond is spring fed with a steady trickle in and one end and out to a field ditch/stream at the other, so water is constantly moving, rarely freezes over and is very clear.

I have always understood leaves in the pond can poison the water for fish, but surely a certain amount of detritus is needed by the bugs and insects on the bottom? Should we be removing the leaves or let nature take its course?

[nightshade]

I always cover my pond and remove any large amounts of detritus
the one time I did not the pond iced up and despite keeping a
breathing hole free of ice many fish died
I keep the pump running so oxygenated water runs back via a gravel
"stream bed" some 2mtr long not dissimilar to your own set up the
pond has a good head of inverts.

[juliejam]

I put in a small pond about 6wks ago..and Im finding
that each day i need to remove the fallen leaves...as the whole of
my garden is surrounded by trees...plus the fact it doesnt look to good.

I read somewhere that fallen leaves can choke a pond of its
oxygen that is needed for pond-life..

Im sure an expert on this matter will be on later and can fill you in
on this..

Julie

[Purplepixii]

I don't doubt that leaves in a pond aren't really a great thing, but who goes round skimming leaves from ponds and streams in the wild...?

Wildlife lives in the wild where nobody puts up nets / skims for leaves and it survives...

I do skim my pond every couple of days, but I know leaves do go to the bottom. And nothing has died yet (fish or frogs).

Just my thought
Purplepixii

[galanthus]

In the wild the leaves usually either fall onto a large body of water like a lake or they fall into streams. Either way they wouldn't accumulate in very large amounts and decompose enough to effect the water life. In many small or medium ponds the oxygen and water content is less and therefore the amount of decomposing leaves it takes to taint the pond is smaller. Therefore, would defo think about skimming the leaves when you can, I use a small net. Otherwise you'll end up with very smelly, unhealthy sludge yuk !!

[naturelover]

when i lived in chelmsford i had a large pond under a large silver birch and you know how small their leaves are,every morning i would skim the top for leaves,if you do this daily its a lot easyer as they dont sink.

[paulchandler6]

I tend to skim the leaves off on a regular basis before they sink.

Paul

[Dogghound]

Leaves do change the ph of the water as well as the oxygen content, wildlife would be ok without excessive amounts of leaves, but its fish in a small pond that would suffer.

[Cotham Marble]

Originally Posted by werdnal

I have always understood leaves in the pond can poison the water for fish, but surely a certain amount of detritus is needed by the bugs and insects on the bottom? Should we be removing the leaves or let nature take its course?

There’s a recent discussion about this at: Pond restoration - advice needed

“Wildlife lives in the wild where nobody puts up nets / skims for leaves and it survives...”

The number of ‘natural’ perpetual ponds which have no energetic inflow and outflow is quite small and their occurrence requires some unusual geological and/or topographical conditions. Most ponds in the UK are the result of human activity and those that do not get at least a seasonal ‘flushing’ are often adversely affected by detrital build up.

Seasonal ponds, or perpetual ponds that go through seasonal changes in depth which cause exposure of all or part of the pond bed are less affected by detrital deposition because exposure during drought allows aerobic decomposition of the deposits. The threat to a pond’s faunal population comes primarily from the anaerobic decay which reduces oxygen levels and can cause a build up of toxic gases.

CM

[Drewsta]

I think part of the answer is dependent upon your own preference for the pond - aesthetic value Vs. natural processes. In most cases a balance between the two is desired, particularly with artificial ponds, and therefore their longevity and precise form requires some management.

Leaf litter is important in ponds as their breakdown is important for energy flow and nutrient cycling, supplying a source of food for some invertebrates and other detritivores. But like you and others have already mentioned, a surplus of decaying leaves do have the potential to reduce the oxygen of the water to low levels, which can be threatening to the fauna. So I would recommend removing some of the leaves but not all, allowing some to decay and become part of the pond ecosystem.

[oakwoodbank]

Originally Posted by Cotham Marble

There’s a recent discussion about this at: Pond restoration - advice needed

“Wildlife lives in the wild where nobody puts up nets / skims for leaves and it survives...”

"The threat to a pond’s faunal population comes primarily from the anaerobic decay which reduces oxygen levels and can cause a build up of toxic gases."

CM

What prevents these gases moving to the surface and escaping?

[bobolovski]

Hi,

By reading previous posts I think it really depends on the size of your pond and what you want from it.
I never clear the leaves out of my pond (which has fir, apple and maple leaf trees around it) and find the leaves settle to the deepest point (around 3.5ft) which i never get to see as its covered by floating water plants and lilys.
The pond is lively and i get regular fish breeding and a great range of invertebrate life.

There is some nasty smelling stuff down the bottom which is to be expected but it doesnt seem to impact the fish one bit.