Pond Boss Forums MANAGING AN EXISTING POND Fertilization which Fertilizer?

I live on an 8 acre pond that was not fertilized last year and now FA is growing from the shore out to about 2 feet deep. I know I need to get back on a fertilization schedule fast but do I use 20-20-5 or 10-52-4? From what I've read there also seems to be a big difference in how much to use. I've seen 40#/acre for 20-20-5 and as low as 8#/acre for 10-52-4. I'm looking to promote fish growth and keep the FA down. Thanks!

If the FA is in that shallow water, I doubt that fert. will do much for that. To keep down the deep rooted stuff and to gat a good bloom, I would suggest the high middle number fert. Phosphate is usually all that is needed in most cases. The N2 will just grow more vegetation. If the 10-52-4 is water soluble fert. I would only use about 3 to 4 lbs. per acre. Triple super phosphate after if needed to kick it up a notch.

BTW...what is your hardness/alkalinity?

Not sure on the hardness/alkalinity. I'll pick up a test kit and check. Thanks for the info.

See this starting on pg 16.

http://msucares.com/pubs/publications/p1428.pdf

Sorry to disagree...but you have your information backwards. Nitrogen fertilization will promote the desirable micro-algae, and Phosphorus fertilization encourages FA and macrophytic algae. Typically, you want 10-200x more N than P in your fertilization additions to make good blooms to produce food chain plankton organisms for fish fry. Check any of the numerous references by David Culver at Ohio State for more specifics. If you can't use white amur to consume the FA (at stocking rates of 15-30/acre), then stick with blue pond dye to shade out some of it.
---Dr. Dave

Dr.Dave this is a kind hearted bunch of folks so I mean no disrespect but you came to the wrong forum to start with this line of thought. This is the kind of post that causes me to pause and question. You gave an opinion and made it seem others were wrong.
I don't understand a post about something that is in conflict with the rest of the pond management world. I just ordered about $30,000 of our blend of 10-52-4. We spend lots of time and lots of years here to teach people about the proper ways to manage ponds and your post seems to be about a localized situation. Phosphorus is the limiting nutrient in most ponds...not nitrogen. I think it would be wise of you to look through this website before you suggest the advice you offered.

As usual it all depends and it depends on several if not numerous things based on the limnology of the pond, water shed and water chemistry. Many fertilization scenarios are possible each in different water bodies depending on water chemistry conditions of each water body. What works in one may not work well in another. Sometimes systems are N limiting, sometimes P limiting, and sometimes macro or micro-nutrient limiting. Sometimes existing plant growth will limit phytoplankton development despite adequate fertilization and proper water chemistry. Ever see a pond that did not develop a bloom after fertilizing? In those cases usually something "chemical wise" was not correct in the additives and/or the dissolved solids in the water body. The referenced studies of Culver were conducted in limestone rich soils and nutrient organic sediment rich ponds which can lead to biased opinions based on others areas of the country where watersheds and soils are different. Often a "shotgun approach" (adding ample amounts of each) is used hoping to get a bloom which very often works well. Degree of alkalinity of the receiving water body can play a big role in developing a bloom and amount of N and/or P needed.

Sometimes when filamentous algae has gotten a good start in the pond, it is sometimes beneficial to kill it or somehow suppress it first, then fertilize so there is not so much FA biomass present to consume the majority of the added fertilizer and stiffle the desired development of a bloom.

Bill, are you or anyone else familiar with a good chart or other resource one can look at to decide what fertilization style is best for their pond, based on a water and/or soil test? Fertilization seems to be a pretty common question on the forum.

To my limited knowledge of the topic I know of no good chart. IMO this is due to the wide differences and variations in water bodies - too many variables for a simple chart. Most often the high P concentration mixture that GG mentioned works well. IMO one of the most important things to do when going to fertilize is FIRST make sure the alkalinity of the water body is at least at the minimim concentration which I think is 50mg/l (50ppm). When exceptions or no bloom occurs then one has to start looking at most probable reasons.

The references by Dr. Dave (not our Dr. Dave from SDSU) are mostly about eutrophic, limestone-based Ohio ponds that are not necessarily applicable to ponds all over the nation. Dr. Dave is absolutely right...if you are in Ohio with limestone based ponds. Greg, although a bit harsher than he normally is, is correct in his assessment (I chose to moderate him a bit...) in that nitrogen is not necessarily the limiting nutrient for most United States ponds. Much of the time, phosphorus is the limiting factor that prevents healthy plankton blooms. Use pond dye if you wish to pre-empt heavy algal blooms or if you wish to pre-empt the base of the food chain for young of the year fish. As Cody says (which is correct), "It all depends." Of course, he has become famous for that line...and he is correct. Plus, we can always count on Eric to help us with good information, too.
Nitrogen has never been a limiting factor in any water in which I work. There's enough nitrogen dissolving from the atmosphere as well as from organic matter in runoff to contribute to heavy filamentous algae blooms in waters I manage. When I see a 'good' plankton bloom, it is the result of adding soluble phosphorus to a pond at the right time at the right temperature.

15-30 white amur per acre to contol FA is also in contrast with all recommendations I have seen. It has been reported that FA is one of the last items on their menu, and numbers such as 5 per acre are given. I personally would much rather combat FA manually or chemically than stock 30 grass carp per acre.

Yep...I missed that point. Grass carp won't control filamentous algae in recreational fishing ponds at all. They physically can't eat it.

Hmm...tail tugged this morning- first time being moderated. I honestly thought Dr.Dave was pulling our chains, it seems the local info he provided was right on. Dr. Dave I learned the lesson of local knowledge years ago when I started posting here. What I do here in SE does not apply all over the US or World. I rarely tackle a "yankee" question these days due to my lack of knowledge there.

I noticed the grass carp rec. as well but did not make a comment. I see where he is going though if you want to control FA you do have to have higher stocking densities. I have seen this work on golf course ponds. I agree Burger i would not want to do that either in a pond managed for fishing.

Sketter Joe , who ask the question is in SC. I don't know what his situation is so "it depends " is good advice. For example we have 3 ponds within a mile and all 3 have different responses to the same mgt practices. I too have not seen a pond that was N limited but don’t doubt they exist. A good idea is to get the soil/water tested so you know the facts. The link I posted makes that clear.

Pond Boss article pending? I'd love to see an article (or series of articles) about this Eric and I'll bet I'm not alone.

Greg, you are agreeing with a good many of my posts lately; scary for you. You also post when I am a little off track, though. Appreciated. Sometimes we personal 'pond bosses' comment on our experiences without looking at the whole picture, such as what Dr. Dave did. Everybody learns on this site.

There are at least a couple applications / situations where pond dye will not work well to control FA. 1. ponds with a measurable inflow that reduces the retention time of the water body. Ponds where the dye concentration is not high enough - too weak, too aged, too diluted. 3. Not all FA is the same species, genus, class or even Division/Phylum of algae. some algae are more tolerant to the light that the dye does allow to pass through the water column.The dye filters out specific wave lengths of light. It all depends.

In my experience, grass carp will sometimes eat certain species or genera of FA algae. It all depends. Not FA algae are the same. The algae species I think the GC will eventually resort to eating are those with coarser fibers/strands and those that have a mild flavor - Cladophora and Pithophora are two examples of genera. Less favorable FA for GC are very fine stranded and slippery feeling genera such as Spirogyra and Mougeotia. Who wants to eat plants that have offensive flavors or stuff that tangles and lodges on the gills rakers and filaments? Some of the filamentous Bluegreens (Cyanobacteria) are now known to produce toxic substances to other animals (mammals and fish) to the point of making them sick or causing death.

I hesitate jumping in on this thread, because I'm pretty ignorant regarding water plants--this being my first pond. I'm familiar with legumes and other land plants that fix nitrogen in conjunction with various bacteria. And I think Azolla is a common water plant that can fix nitrogen in conjunction with cyanobacterium. Are there other plants or bacteria present in typical ponds that contribute significant nitrogen in the presence of the oxygen levels typical in ponds?

A "google" revealed this. """ However, atmospheric nitrogen is unavailable for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. Although earth’s atmosphere is an abundant source of nitrogen, most is relatively unusable by plants[3]. Chemical processing, or natural fixation (through processes such as bacterial conversion--see rhizobium), are necessary to convert gaseous nitrogen into forms usable by living organisms. This makes nitrogen a crucial part of food production. The abundance or scarcity of this "fixed" form of nitrogen, (also known as reactive nitrogen), dictates how much food can be grown on a piece of land.""" from:
http://en.wikipedia.org/wiki/Nitrogen_cycle

I do know that some bluegreen algae (Cyanobacteria) can fix nitrogen from the atmosphere. As far as I know most N (available nitrogen) that is available in natural unpolluted waters is from animal wastes byproductes (ammonia, decompostion, death, decay processes). Animals being bacteria to predators.

From:
http://www.visionlearning.com/library/module_viewer.php?mid=98

""In fact, in order for plants and animals to be able to use nitrogen, N2 gas must first be converted to more a chemically available form such as ammonium (NH4+), nitrate (NO3-), or organic nitrogen (e.g. urea - (NH3)2CO). The inert nature of N2 means that biologically available nitrogen is often in short supply in natural ecosystems, limiting plant growth and biomass accumulation.""



Research has revealed some other items on this topic:
Nitrogen fixing bacteria associated with duck weed:
http://aem.asm.org/cgi/reprint/43/4/823.pdf

Another N fixing source:
http://www.sciencedirect.com/science?_ob...0fbef26560ff35b

Many of the peas and some clover will fix N to the soil.