Pond Boss Forums INTRO Questions & Observations Nutrient balance in buffer zone

I understand that a buffer zone around a pond (1/4 acre) serves to remove some surface flow silt and dissolved nutrients. But when those plants die back in winter and begin to decompose, won't that just reintroduce those nutrients to the inflow? Should those plants be trimmed back with trimmings removed from the area? Is it worth the work required?

You are correct that you absolutely need some plants surrounding the pond.

They stop erosion on the slopes to the pond and tend to catch any silt that is suspended in the surface run-off water after heavy rains.

They also slow the incoming surface water, which greatly increases the infiltration rate of that water into your soil. That is the process for keeping some of the dissolved nutrients out of the pond.

(Judging by the language in your post, I am pretty sure you already knew all of that.)

Addressing what happens to the nutrients when your plants die back in winter, is highly dependent on what type of plants you have in your buffer zone.

If you have shrubs or trees that shed a lot of leaves or needles that can easily be blown into the pond, that is a net negative.

If you have grasses, they will largely decompose in place. My native tall grasses form a natural thatch over the years. We try to burn every 4-5 years to combat the lost productivity due to the build up of thatch. (We don't burn any of the grassed waterways leading directly to my ponds.)

Likewise, you can probably observe the build up of thatch in the parts of your lawn that you mow. However, a good mulching blade will help get most of that into small enough bits that it will decompose in place, rather than forming a thick thatch. (I don't know if you mow around your pond.)

I believe that you have surmised that a heavy rain in the winter will actually float some thatch (and nutrients) into your pond. However, I think that is usually a minimal transport of nutrients.

IMO, if you want to go for maximize nutrient exclusion, I would mow and bale (tall grass) or mow and bag (short grass). If you are not selling the bales though, that is a lot of work for only a little benefit.

If you want a partial solution, then you could mow some strips perpendicular to the slope and leave unmowed grass strips in between to catch any organic debris before it enters the pond. This is similar to the "silt fencing" you see around construction projects where the work created bare ground.

This method does look goofy, especially if your wife likes looking at a well-manicured pond setting from your deck. However, all of the wildlife on my farm loves having mowed areas in between tall grass areas. The deer, turkey, quail, and even the coyotes love traversing the property in the short stuff, and then as soon as they sense any danger they fade into the adjacent heavy cover.

I don't know how much of that long reply actually applies to your situation? Hopefully, you can find some little bit that actually is helpful to your pond management situation on your property.

Have fun keeping your pond in good shape!

I have plenty of weedy grasses. But, I still scratched the ground and spread a bunch of Bermuda seed

Thanks for your thoughts. I'm mainly trying to calibrate my brain to be able to take care of the most important things first, then work on others as I see the pond responding. The pond area was all wetlands (about a 1/2 acre) near where I am building a home (the non-wetlands part of a 4 acre rural lot). Under an Army Corps of Engineers wetland permit i excavated the central part of the wetlands 4 years ago for the pond. My goal is to disturb the property as little as possible and maintain the pond as naturally as possible. There are several trees nearby and I have already realized that I need to remove/prevent as much of the fall leaf litter as possible from affecting the pond. I will be adding aeration soon when power comes to the house site. The current question was posed to help determine if harvesting potential nutrients from the "natural" wetlands growth, vs leaving nature alone, was going to be necessary. From your comments I believe I will watch and see. I'm not looking for a manicured lawn down to a thin line of pond-edge plants. I much prefer watching nature do its thing. I will likely weed-whack a few key areas and shoreline access points, but hope to avoid doing more than that.

I have a small area of ephemeral wetlands on our property. During dry periods it isn't very noticeable, unless you are observing the plant species. You can walk from all of the grasses and forbs in our tallgrass prairie into an area with dozens of different species that thrive with "wet feet".

If your wetlands are natural, then they are probably hundreds or even thousands of years old. In that case, your pond will almost assuredly be eutrophic (high nutrients).

You will probably fight algae problems when your pond is young, but that should subside later as rooted pond plants native to your wetlands re-establish in your pond and start "stealing" nutrients from the algae.

I like your plan to cut a few access trails and then observe the changes, and THEN make modifications from that point.

I think your pond will always have nutrient-rich water. Your achievable goal will then probably be to minimize the buildup of organic muck on the bottom of your pond that slowly tries to make your pond shallower. Clearing the trees that will contribute organic matter is a good start with a large benefit for not that much work.

The other thing to manage may be to knock back some of your pond plants early in the growth cycle to reduce the total annual mass of plant material. I would recommend coming back later to the forum and getting a correct identification for your plants, and then some treatment/control recommendations (if needed). There are several excellent pond managers and even professionals on Pond Boss to give you advice on that topic.

I hope you enjoy the home build project coming up now!

I also agree with your plan to "disturb" the natural beauty of the property as little as possible. However, it is possible to enhance the natural beauty with just a few gentle nudges. For example, if your wife does want a few trees, you could plant a few bald cypress trees at the edge of the wetlands that would enhance your view in a location far enough from the pond where the needles won't easily be transported that distance. Those trees should thrive in that environment and grow relatively rapidly to replace the trees you cut adjacent to the pond.