Management Plan

Aquatic plant management: management plans

What is a lake management plan?

A lake management plan is a “whole lake” document. It points out goals for cultivating desired lake and watershed conditions for a time period. A lake management plan can include many things, but is often focused on an aquatic plant management plan. Management plans also inform decisions around treatment strategies. They help show which management strategies are appropriate. Examples are: mechanical, hand harvesting, drawdown, bottom barriers, pond dye, herbicides and algaecide. Longer-term management strategy examples are: biological control, nutrient/watershed management.

Many lake property owners and groups (hereafter, “stakeholders”) get annual aquatic herbicide treatments. However, re-treating every year without assessing if goals are met is not beneficial. This can actually harm the lake. An aquatic plant management plan clears up goals for lake management. It guides if treatment is needed and if management is working. Stakeholders should have an aquatic weed control plan even without invasive aquatic weeds. A management plan should make steps to stop new nuisance pond weeds. It should provide an early detection and rapid response program for the waterbody. This helps new plants be managed quickly at lower cost by identifying problems early. The plan should also identify resources and stakeholders. This helps coalitions to be built to aid in the management of problem species.

Rather than using a single treatment approach (such as aquatic herbicides or using a lake weed rake), many water plant management plans now use “integrated pest management”. This approach includes the following:

• Identify the invasive or nuisance aquatic plants using a plant survey
• Point out desired submerged aquatic vegetation (and other plants) to reach fish and wildlife habitat goals
• Decide acceptable levels of any single plant species. Include target nuisance lake plants
• Making decisions based on site-specific information
• Use ecosystem, watershed, and cost-benefit focus for long-term management strategies
• Plan future integrated aquatic weed control methods that include mechanical, cultural, biological, and chemical treatments as needed
• Teaching local managers and the public how to protect water resources from invasive weeds to maintain healthy water quality and fish and wildlife habitat
• Watch results of invasive aquatic weed control programs (including documentation of results of all aquatic plant control strategies), and re-evaluate management options

Benefits and drawbacks of a lake management plan

Lake management plans can point out the best treatments for invasive aquatic plants. For example, aquatic plant surveys show where beneficial native aquatic plants are growing. They also show where invasive lake weeds are growing. Lastly, they show where there is a mix of native and invasive lake plants. This will inform which treatment strategy will work best.

Lake management plans also involve a water quality analysis. This shows whether the plant issue is actually due to nutrients. Phosphorus and nitrogen have been known as key causes of nuisance growth of lake and pond weeds, algae, and blue green algae in inland lakes. These nutrients can be reduced by: 1) Checking that septic tanks are working; 2) avoiding the use of lawn fertilizers that contain phosphorus; and 3) preserving riparian vegetation buffers around a lake. These buffers act as filters for land pollutants that may run off into a lake. A lake management plan will show the cause of the problem and allow stakeholders to fix its source. This may lead to fewer nuisance water weeds.

While lake management plans improve lakes, they may cost more upfront. Also, they may take longer to begin treatment than a routine herbicide application. However, the “whole lake” approach addresses the root cause of the problem and adjusts the lake weed control method to be effective. Therefore, it will likely save money and effort in the long-term. It may also help your lake get new sources of funding for lake management activities.

Many lake management service providers offer many options and will work with lake stakeholders to find funding to develop lake management plans. This will lead to better long-term outcomes. There are several support options that may also help with funding. Examples are local organizations (watershed/conservation groups, community foundations, local government public works authorities), institutional support (University/Sea Grant Extension), state agencies (DNR/DEQ data and grants), and federal support (Clean Water Act Section 319 watershed funds).

How to develop a lake management plan?

While lake management plans can be made by the lake stakeholders, they require significant training and scientific background and are usually prepared by a professional. Many companies provide lake management services (hereafter, “lake management service providers”) that will assist a lake group with preparing a lake management plan. These lake management service providers are different from treatment applicators (someone who does the actual treatment, e.g., applies the herbicide or algacide). While some lake management service providers also conduct treatment, this can result in a conflict of interest. By keeping them separate, the lake management service provider does not benefit from recommending treatment (which costs money). Ideally they will recommend what works best for the lake. Having a separate lake management service provider to evaluate optimal treatments will ensure they have the lake stakeholder’s best interests at heart.

How to find a lake management service provider?

When looking for a lake management service provider to prepare a lake management plan and help decide how to treat invasive aquatic plants, there are several things to consider. One consideration is the approach of the service provider. They should have a “whole lake” approach. This focuses on the many parts that make a healthy lake. One “red flag” is if they begin lake weed killer treatment before first doing macrophyte survey to see which plants are in the patch (i.e., is it all invasive water plants, or is there a mix of invasive and native water plants). Another red flag is a service provider that just treats the pond weed patch without considering water nutrient levels (which will lead to the need for repeated treatments due to excessive plant growth) or if there are other invasive plants nearby that will just spread back to the treated area (again, leading to the need for repeated treatments). That approach only considers short-term costs and may cost more in the long run. When finding a “whole lake” service provider, some questions to ask are:

• Do you prepare lake management plans as well as do treatment? This may be a conflict of interest as noted above. Many lakes hire the lake management service providers apart from the treatment applicator.
• Do these lake management plans involve aquatic plant surveys before and after treatment? 
  • Surveys should be before and after treatment to see how the treatment worked. This helps decide if it needs to be modified for the next season.Do they involve the lake community? 
    • Lake management plans are better with buy-in from other stakeholders.

• What other lakes have you helped manage with success?
  •  In particular, stakeholders should ask service providers to provide example of clients who have had similar problems to the stakeholder’s lake.

• What are your credentials?
  •  For the lake management service provider, it is best to have a Masters or PhD degree and a Certified Lake Professional (CLP) or Certified Lake Manager (CLM) from the North American Lake Management Society (NALMS).
  • Selection of a treatment applicator is more straightforward. The lake management service provider will recommend which treatments to use.