Hydrilla verticillata (lakeweed)

Background – The Lake House

My wife’s parents live on the Tennessee river. We have for years gone there and played on the water. Swimming, boating, fishing enjoying the view and whatever else people might do at the lake.

Hydrilla verticillata, lakeweed
This is an image of the lake weed in the winter when it is less prevalent. If I remember I will get some summer photos next summer out on the water. It can be seen that it captures trash as well creating an ugly viewshed. Even the Canadian geese have avoided swimming where this plant is present.

The Problem – Lakeweed (Hydrilla verticillata)

I’ve previously mentioned that I am an environmental guy. This last summer I became aware of a lake problem in my in-laws backyard. Lakeweed is an aquatic plant from Asia (why do the bad invasives all seem to be from Asia?). It grows under the water unseen until it reaches the surface and the rapidly spreads to cover the surface. This dense growth inhibits water recreation, can increase water pH, blocks sunlight to native plants and can even disrupt fish and plant species diversity within an ecosystem.

Lakeweed is able to grow at depths of 45′ and reach the surface. It can tolerate some salinity and it is incredibly difficult to eliminate in eastern North American freshwater systems. Biocontrol has been attempted though it is still too early to determine if the biocontrol will be successful. Chemical control is available but involves filling the entire water system with chemicals and treating for a decade.

If you read my post about Hemlock Wooly Adelgid then you understand I am not the biggest fan of biocontrol. In the instance of lakeweed I am for anything that works. This plant threatens the entire freshwater aquatic ecosystem of the region and a significant portion of the economy around water recreation and the barge transportation industry.

The Solution – Farming Biomass

While I am really unhappy with this particular invasive plant everything I found in the literature (a short search on google scholar) was focused on eliminating the plant. The methods of eradication are both expensive and longterm and may have drawbacks. I would like to propose an alternate solution to the lakeweed problem, farming.

Hydrilla was introduced in the 1950s to Florida and initially it was farmed. Then it got out of control and became a pest. Since that time the government has made it illegal to sell the plant because of how invasive it is considered. Fast forward to modern times it seems that we are using an outdated approach to address the problem. We are still doing the man can control nature system. This approach while doable is not the best approach. Consider the levy system in New Orleans …nature won. What about Fukushima? Nature won again. Kudzu? Nature. There are many examples where man tries to tame nature only to great disaster when nature wins or man wins too well.

The shift in thought is a new way of looking at the problem. Instead of focusing on eliminating the problem perhaps it is better to accept that we have a problem. Accept that it is a huge problem and will be very costly (if it is even possible) to correct. Move a step forward and ask a new question “How can we benefit from a lakeweed problem?”.  Currently aquatic harvesting machinery can cut and collect the plant matter. One of these aquatic harvesters can be purchased for as cheap as $50,000. The next logical step is that the plant matter needs to be collected and removed from the waterbody to prevent clogs etc..

My solution would be to collect this biomass and figure out a way to turn it into biodiesel or burn it to produce electricity. I have not examined the profitability of this proposal but homeowners spending $300-400 three times a year to cut the lakeweed (a 3-4 hour process), and chemically treat around their docks just to gain access to the main channel is not a good solution. A biodiesel production program or electric generation program run by either Tennessee Valley Authority or the Army Corps of Engineers to actively farm the waterways (which they already control).

A program could either significantly reduce the costs of cutting the lakeweed and thus mitigate the cost of remediation. Alternately if the farming can be made profitable then perhaps the plant can be allowed to remain in the ecosystem and regular rotations for cutting can be developed to maximize recreational use, ecological benefits, and profitability.

Conclusion – Work with not against Nature

I think the key concept to get from this is not necessarily the details on generating profit from a disaster (that can probably be accomplished), such as lakeweed, but rather to shift our thinking as a society from trying to fix disasters to a work with nature approach. I think some environmental professionals probably share this view others probably disagree but it is probably a view that should become more common (in my opinion) because it allows for system that works more cohesively together.

Hemlock Woolly Adelgid

Background – The Forest

In the eastern portion of North America there is a tree biologists know as Tsuga canadensis. The common name for this tree is the Canadian hemlock. You can read more about this tree and other  plant species in A Field Guide to Eastern Trees: Eastern United States and Canada, Including the Midwest or Guide To The Trees,Shrubs & Woody Vines of Tennessee. It is a unique tree in the forest and provides specialized habitat for other species. Typically in the Appalachian mountains the tree can be found inside sloping valleys above mountain streams.

A local Canadian Hemlock in a front yard.
A Canadian Hemlock in a front yard down the street from my home. In some forests that can be a very prolific species.

The Problem – Hemlock Woolly Adelgid

Hemlock Leaves
Healthy Hemlock leaves  Sorry it is blurry my camera doesn’t like close-ups.

Unfortunately, there is an aphid (a small sap sucking insect) which was introduced to North America from Asia. This aphid is called the Hemlock Woolly Adelgid (Adelges tsugae). This is an example of an exotic pest like many exotic species it has become problematic. The aphid kills hemlock trees and has been doing so for approximately 60 years in the Appalachian mountains. Initially the tree looks healthy then it develops white spots underneath the foliage. These white spots are actually the egg sacs of the aphids. The aphids bite the leaves at their base in order to get to the sap. Because of the damage to the base the leaves fall off. Within five to ten years the tree will die.

woolly adelgid on hemlock leaves
Hemlock leaves with woolly adelgid, see the white spots on the twig adjacent to the leaves. The white blobs are the egg sacs.

The Solution – Combating the Hemlock Woolly Adelgid

Currently there are two different approaches for controlling the aphid population. First, a chemical treatment can be applied to the tree. This will travel through the vascular system of the tree and when aphids eat the sap they will die. Using this technique trees can be protected for 5-10 years at a time. The major downside to chemical treatment is that harsh chemicals are introduced to the environment and may cause additional problems down the road (especially if used repeatedly and in large quantities).

A second major approach to combating the aphid is biological control. Biological control is utilizing another species to control a problematic species. I must admit anytime biological control is mentioned I shudder and I did not disappoint in this instance. When biological control works it works with great effectiveness. Consider, if one species is allowed to eat another species and multiply then it will continue to attack the species for a long time.

The problem with biological control systems is that when they fail they often do so by creating an entirely new set of problems. Often attacking other native species or out competing them. The problem is that once the species is loose and breeding in the wild it is virtually impossible to eliminate without severe destruction in the environment.

Once I learned that biological control was being used with hemlocks I was immediately concerned about this approach. I then read to learn what sorts of biological control were being utilized. Fortunately it appears that current approaches to biological control require a species to get approval. In order to get approved the species undergoes rigorous testing to attempt to determine any possible problems that may arise. Currently desirable traits for candidates for biological are that they are very specific in the species that they attack. This presumably limits the potential for problems.

A better solution in my opinion is genetic modification of the hemlock species. This can be achieved by two different methodologies. One process involves a breeding program where trees which can breed with the hemlock and have demonstrated resistance to the pest are combined in order to produce resistant children. A second process involves lab based genetic modification using sophisticated equipment and techniques. Both approaches are expensive and require a lot of work by scientists.

Conclusion – The Cat is Out of the Bag

In the case of the Canadian hemlock biological control is already underway and that means we can only wait and see how it ends. Hopefully it ends well and without problems. In my humble opinion biological control should be a last resort.  The species genetics can be protected with chemical treatment in isolated areas in controlled conservation areas. This allows time to approach the problem

Another Canadian hemlock in the neighbors front yard
Another Canadian hemlock in the front yard of a neighbors house.

genetically though there could be problems to other species which depend on the hemlock. Provided a plan with the chemical reagent can be implemented to protect the species genetics and other dependent species. Then genetic modification is a superior approach but it may take decades to accomplish.

Drive-Through Windows – Solution A Day

Background – Fast Food Dinner

Car sitting in the drive through.
A local krystals drive through.

A few weeks I drove through a McDonald’s restaurant and I went to the speaker and ordered my food. I then went to window one to pay and then to window two. while waiting at the windows.

The Problem – The Drive-Through Windows were left open

window left open
The Krystal’s window can be seen left open.

While at the windows for the drive through I observed that the customer service attendant kept leaving the window open. In fact it was open for more than 50% of the time that my car was at the window. I admit that I have not done a comprehensive study about how frequently drive through windows are left open. However, I have 30 years of experience as a consumer and can recall many occasions where this practice was par for the course. The main problem is that for a good portion of the year restaurants (or rather their owners) are spending money to keep their establishment climate controlled. Leaving the window open unnecessarily adds to the amount of energy used for climate control. In many cases this energy is in the form of electricity. Frequently this electricity is created by burning fossil fuels. Waste like this can significantly add to the total carbon emissions entering the atmosphere. These carbon emissions then add to global warming. Consider that there are more than 200,000 drive-through establishments in the U.S. alone. This is a huge total effect.

I like to promote protecting the environment while simultaneously benefiting people and protecting your pocketbook. This wasteful energy is a direct burden everyone involved. If a business needs to spend an extra $2000 a year on electricity because of this window then they must increase the cost of whatever product they are selling in order to make a profit. The increase in cost is passed on to the consumer who ends up paying for the wasted energy. Remaining competitive in an industry such as fast food absolutely requires keeping costs in check. Fixing the window problem will help with this goal.

The Solution – Close the Window

Perhaps the easiest and cheapest solution is for business owners and managers would be to create and enforce operating procedures to ensure that floor level employees close the window. This is every bit as bad as the 2008 discovery that starbucks was wasting 6 million gallons of water daily in the U.K. by leaving their tap on. A more expensive (but possibly more effective) approach would be to install windows that automatically shut. For the business owner either of these solutions will reduce the bottom line and increase profits. The reduces costs will increase competitive edge either with better paid staff, cheaper prices, or increased profits.

Conclusion – Shut the Window

Shutting the window will save money for everyone. It will also improve the atmosphere for generations to come. If you are an employee who works at a drive through window please remember this the next time you clock-in. I want to stress that many of the environmental problems I talk about are not limited to one company. Rather I mention larger companies because they are present everywhere. In other words while McDonalds and Krystal’s leave their windows open so do many other unnamed companies and Starbucks isn’t the only company who has problems recycling hot beverage cups and saving water they just represent a large portion of their markets.