Cayuga Lake Inlet: Part II

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1 Fall 2012 Allied Biological's Lake Management Newsletter Cayuga Lake Inlet: Part II In this Issue.. Last winter we reported on the identification and control of the highly invasive plant hydrilla in the inlet of Cayuga Lake. Like most invasive plant control programs, last year s treatment was only the start of a multi-year effort to eradicate this plant infestation, and prevent it from spreading into more areas of upstate New York. To review, hydrilla (Hydrilla verticillata) is an aggressive invasive perennial submersed plant native to Asia, and parts of Africa and Australia, and is thought to have arrived in Florida in the mid-1950 s via the aquarium trade. Since then it has spread up the East Coast to Maine, and out West to California and Washington State. Hydrilla uses several strategies to reproduce. The most common is stem fragmentation, which can occur with as few as two nodes (whorls of leaves). It also spreads via underground rhizomes and above ground stolons. What sets hydrilla apart from other members of the frog-bit family is the production of turions and tubers. Tubers are very hardy, and can remain viable in the sediment for four years, or pass through the gut of waterfowl, and still generate new growth. Tubers are also highly resistant to ice cover, drying, and herbicides. Studies have determined that a single tuber can produce over 5,000 new tubers per square meter. (Continued on the next page) Cayuga Inlet Part II Clipper Herbicide Results Rare plant Waterwheel! Notes Packanack Lake Fish Salvage Project Photo Contest Winners

2 Cayuga Lake Inlet cont d The formation of tubers and turions are one of the main reasons hydrilla can t be controlled in a single herbicide treatment, or in a single season. Following last Fall s Aquathol K application in the Cayuga inlet, a Task Force was formed to design an aggressive management and monitoring plan. In 2012, the Task Force determined that herbicide applications, as depicted in yellow in the picture to the right, would be used to manage the infestation. Monitoring Dr. Robert Johnson, (Cornell University (Retired) the first person to identify the hydrilla infestation, was retained to continue a comprehensive plant and tuber monitoring plan. Dr. Johnson monitored 200 locations in the inlet before and after this year s herbicide treatment, and also surveyed 1,500 locations in Cayuga Lake to determine if hydrilla had spread into the huge waterbody. As a part of each herbicide application, herbicide concentrations were monitored at up to 24 different sites every week. This was done to ensure proper concentrations were met and maintained within the treatment area, and to confirm that the herbicide did not affect water use outside the posted application zone. Herbicide Application Allied Biological applied the contact herbicide Aquathol K first, in late June, to control any spring hydrilla growth in approximately 100 acres of the inlet canal and tributaries. Within approximately two weeks, more than 95% of the hydrilla was removed. Three weeks later, Allied Biological began a two-pronged Sonar application in conjunction with SePRO Corporation. Three injector units supplied by SePRO were placed at the upstream end of the inlet and two tributaries. These units were turned on, and were electronically metered to release the herbicide based on water flow rates for the next four months. To compliment the liquid Sonar injection, four applications of granular Sonar One were applied to areas that contained the densest hydrilla infestations, and areas that the injection did not adequately reach. As of late October, Dr. Johnson had found only a single sprig of hydrilla within or adjacent to the herbicide application area, so the season s herbicide applications have been a resounding success. It is likely that the monitoring plan will continue through next season and beyond, with some provision for additional management work if needed. The City of Ithaca, the Tompkins County Soil and Water office, the Tompkins County Health Department, the New York State Department of Environmental Conservation, Dr. Robert Johnson, SePRO Corporation, United Phosphorus and Allied Biological have all played critical roles in this significant undertaking, and can be proud of the success of the project to date.

3 Clipper Herbicide A Hit! Clipper Herbicide, active ingredient flumioxazin, entered the aquatics market in 2010, and got its first widespread use by Allied Biological this past summer. Clipper is a broad-spectrum herbicide that acts quickly, preventing a plant s production of chlorophyll. The herbicide also breaks down rapidly in water, exhibiting a half-life of only one to five days depending on ph. Clipper is known to provide particularly good control on two invasive species, the submersed plant fanwort (Cabomba caroliniana) and the small floating plant watermeal (Wolffia columbiana). We had the opportunity to use Clipper on fanwort this season at a 25-acre lake in Passaic County, and results were excellent. The application was focused along the shoreline of the lake, at a rate of 0.2 parts per million (ppm). Within two weeks, treated fanwort had lost all vigor and had largely decayed, as had non-targeted bladderwort, white water lily and watermilfoil. The control of bladderwort and watermilfoil was anticipated, but the water lily control was a clear bonus for this lake community. What was even more surprising was the control that extended beyond the shoreline application area to the majority of the lake, making the application particularly cost-effective. Below is a photo of plant specimens taken only one week after the application. Based on the results of this lake, and a similar lake in Monroe County, PA, we extended the use of Clipper, focusing on lakes with bladderwort problems or with shallow plant beds that the herbicide Reward sometimes fails to control. At every site where Clipper was used, plant control was excellent, and often much better than previous Reward applications achieved. Clipper is registered in New Jersey and Pennsylvania, but is still pending registration in New York. Hopefully, New York registration will come soon, since fanwort infestations are widespread on Long Island, and watermeal completely covers many ponds throughout Orange and Rockland Counties. Clipper provides an opportunity to control these infestations in a targeted manner, and in a very short period.

4 Waterwheel Aldrovanda vesiculosa When kayaking around a lake, it s not often you find a plant that s never been found before. Its even rarer when you, a lake professional, can t identify it. And rarer still, when it can t be found in all of the aquatic plant identification books! That plant is waterwheel ( Aldrovanda vesiculos), and that s just what we found during a lake survey for our Aquatic Flora of New Jersey project. Waterwheel is a free-floating plant that looks like a type of bladderwort. In fact, it is a carnivorous plant, but more closely related to the Venus Fly Trap. It ensnares prey in a two-lobed trap which closes as quickly as 0.01 seconds (1).The plant prefers low ph, shallow, warm waters that are high in humic acid, and is typically found among emergent plant stands. We found it in exactly that type of habitat, on the edge of a 100+ acre lake in Sussex County, NJ. It was floating with other native plants such as common duckweed, giant duckweed and spiny hornwort. So, what makes this plant so unusual? It is native to Europe, Africa, Asia and Australia, and it has not yet been officially documented by aquatic botanists in North America! Even in its native range, the plant is almost extinct, believed to be found in less than 50 sites throughout its range (2). After a little internet research, we re pretty confident it came to New Jersey through the aquarium or water garden industries. In fact, one carnivorous plant aficionado reports to having grown it for resale in a pond in Succasunna, NJ. Likely it was spread by waterfowl from Succasunna to northern Sussex County. So now what? We ve reported the find to regional aquatic plant botanists, and to the NJ Natural Heritage Program. Of course, the Natural Heritage Program focuses on native species, not rare exotic species, so we ve also reported the find to the NJ Invasive Species Strike Team. At this point, waterwheel does not appear to be growing invasively in this Sussex County lake, so no control efforts are expected. Instead, we look forward to next Spring and searching neighboring lakes for more waterwheel. (1,2) Aldrovanda, The Waterwheel Plant, by Adam Cross, May, 2012

5 Notes So long Shallow Water Harvester Sometimes good intentions are just not enough, and we lay an egg. Such is the case with the Shallow Water Harvester. r. We purchased the harvester with the plan to offer weed ed control in areas where herbicides couldn t or wouldn t be used, and where larger harvesters couldn t reach. That approach was sound, and in fact, requests for the machine far exceeded our expectations. Unfortunately, the machine itself failed to make the grade. From an engineering design standpoint, the machine fell short. The rotating drum pulled plants, but only in the softest mud did it actually dislodge roots. Its claim to operate in 18 of water was in reality 24 of water, and a dry spring kept us out of several waterfront properties. Over the first two weeks of operation, we were also plagued with a series of mechanical failures. A motor that operated the paddle wheels continued to come loose. We found that several of the lubricating points were inaccessible, and these had to be lubed almost every day. We also experienced a frustrating number of small, but persistent hydraulic leaks that eventually lead us to park the machine and discontinue its use. So, where to go from here? We have made arrangements to return the machine and look for a new and better small harvester to meet our growing needs. For those of you we were unable to help this season, we appreciate your patience and offer our apologies. When we arrive at a responsible solution, you will be the first to know. Welcome Clean Lakes clients! This past Spring, Allied Biological was fortunate to sign an agreement with Rebecca Withers of Clean Lakes, Inc. to assume management of her lake clients upon her retirement. We are happy to welcome our new lakes and new friends, and wish Rebecca and Bill a happy and active retirement! Garrison Pond Green Mountain Lake Loch Lyall Lake Lost Lake McAuley s Lakes Merriewold Lake Lake Osiris Round Lake Sapphire Lake Swartout Lake Lake Walton Wanaksink Lake More hydrilla in New York This past September, biologists from the US Fish and Wildlife Service reported the presence of hydrilla in the Erie Canal north of Buffalo, NY. The find was confirmed by NYSDEC staff and by Dr. Mike Netherland of the Army Corps of Engineers in Gainesville, FL. Surveys later confirmed that hydrilla occurred in almost 10 miles of the canal. Planning is underway to combat this infestation in Spring, Recently, another new hydrilla find occurred in Windsor, NY, in the vicinity of Rts. 17 and 81. Three separate ponds within a 2- mile radius of one another were all found to contain hydrilla. Identification was made by Allied Biological based on leaf structure and the presence of turions and tubers.

6 Packanack Lake Fish Salvage Project By Chris Doyle, CLM Packanack Lake is an 88 acre lake located in Wayne, New Jersey. In the fall of 2012, the lake needed to be drained to access and fully repair a damaged valve at the outlet structure. As part of their lake lowering permit, New Jersey Division of Fish and Wildlife required the salvaging of as many fish as possible, a task routinely conducted by Allied Biological using its custom-designed electro-fishing boat. Allied Biological had conducted a fish population study in 2010, and our study revealed an overabundance of white perch and common carp, plus a lack of forage species that were detrimental to the game fish population, and likely contributing to persistent phytoplankton blooms in the water column. As usual, the project presented numerous difficulties. It took weeks to find a nearby site to restock the fish, due to the presence of the nuisance white perch. It was ultimately determined the Pompton River would be suitable, as the local population of northern pike would happily add stunted white perch to their list of prey items. Two sites needed to be used to access the lake with the boat as the water receded, and equipment was dragged over the mud on the final days before boat access became impossible. Add Superstorm Sandy and an early season Nor easter snowstorm in the middle of the project, and delays required special extensions to our collecting and stocking permits. All told, over 4,200 fish were salvaged from Packanack Lake. Several hundred of the fish were turned over to the Hackettstown Fish Hatchery for future brood stock, including largemouth bass, black crappie, yellow perch and bluegill sunfish. It was surprising how many black crappie were salvaged (~500) and how few white perch (~400), based on our population study data. But even more shocking was the common carp abundance at Packanack Lake. Over 800 common carp were removed, with most of them between two and three feet long (pictured left). At an estimated 20 pounds each, approximately 16,000 pounds (or close to eight tons!) of biomass were tied up in benthic feeding common carp. It is well documented how destructive carp can be to a fishery, and the general ecology of a lake. Coupled with the presence of a stunted white perch population (also a benthic feeder, and detrimental to a healthy game fish population), it seems clear that the previous fish assemblage was working against many of our lake management goals at this site. On a pleasant note: pulling a healthy 40 inch tiger muskie (pictured right) provided excitement for the netters. Packanack Lake has a rare opportunity to hit the reset button on its fishery in With a sensible re-stocking program, we are hopeful that in a few short years, the game fish population will be robust, and a reduction in the duration and intensity of phytoplankton blooms will create a suitable environment for the establishment of desirable native plant communities.

7 Allied Biological's "A Day at the Lake" 40th Anniversary Photo Contest Thank you to everyone who participated in our "A Day at the Lake" photo contest! We received excellent entries and truly enjoyed seeing the lakes through your eyes. After much consideration, the winners are 1st PLACE 2nd PLACE 3rd PLACE "Daybreak on Truesdale" "An Intimate Moment with Lake Naomi" Cari and Michael Tierney Lake Naomi B. Buckhout Truesdale Lake Paul Christian Lake Naomi Congratulations to the Winners! We have shared all the photos on Allied Biological's Flickr page: