Friday, June 03, 2005

Lakeshores

I got to spend some time outdoors today, in the name of work. I was inspecting lakeshores, places where people have applied for a permit to remove aquatic vegetation so they can swim/fish/get their jet ski or boat out into the water. Unfortunately I can't just rubber stamp a big "NO" on any permit application that involves the use of herbicides. I can understand using a little elbow grease to cut and pull a few plants in a small area, but why it is legal to spray poison in public waters is beyond me. So my job is to make sure that any plant removal is justified, and that the impact to the lake is minimal.

I also don't understand why, when someone from the cities buys a lake lot these days, they feel obligated to clear it, mow it to within inches of the water, put up a barrier of riprap, and put up the kind of landscaping so as to render it indistinguishable from the suburban lot back home. Then they build a mini-mansion to use as their "weekend place". I find the old fashioned, small cabins much more charming, and the visual impact is much more favorable to the up north experience of going to the lake. Now if the septic impacts were only so benign...

My old friend Aphanizomenon is already beginning to appear in the water column. Looking like finely shredded grass clippings, this blue green algae thrives on excess phosphorus and nitrogen from runoff and leaching from septic systems. By mid summer it forms layers of scum tinged bright turquoise, hence the name "blue green" algae. I am not allergic to many things, but I am definitely allergic to this particular algae. Years ago, when I was doing some netting (for work) on the same lake I was at today, I told my partner that within thirty minutes I would be sneezing uncontrollably, and I was right. And that was just from working in a boat on the surface of the water. Swimming in it would require heavy doses of Benadryl. I found out the particular species when I was in graduate school and took a course called "Biology of Algae". Our field work took us to a lake in eastern South Dakota that at the time had the consistency of pea soup. After canoeing out and taking a scum specimen, I was sneezing and rubbing bloodshot eyes in the back seat of the professor's car all the rest of the way to the Black Hills. Microcystis or Anabaena didn't do it; just Aphanizomenon.

I heard two loons calling as they swam and dove out in the open water, but I did not see if they had any chicks yet. Not living on a lake, I don't get to hear their calls too often and it is always a pleasure. And, as I was standing on shore writing some notes, a ruby throated hummingbird came within two feet of me, hovering just inches off the ground, and took a few sips from a Creeping Charlie blossom.

2 comments:

Anonymous said...

Send me the applications, I'll be happy to stamp a big "No" on them. ;) Actually I'd like to stamp something like "If you don't like nature, go back to the city!!" If only all native plant removal was regulated...

Lené Gary said...

Hey Deb,
Thanks for raising the question about herbicides. Just curious what you think about lampricides and other pesticides applied to water directly. Amazing to me.

Anyway, there's a Round-up alternative that may be worth suggesting a look at--Burn Out II. Its made with clove oil and vinegar and has been successful in controling broadleaf species in athletic fields. I know Gardener's Suppy carries it. I don't know if it would be appropriate to the situation, but it may pose less risk than other herbicides.

Our loons hatch, I believe, in late June-early July. I saw two riding their mother's back last year over July 4th weekend, and from what I've read, they only do that for the first 2 weeks of their lives. High mercury levels have been correlated with reduced time spent riding the backs of the adults, which is quite interesting too. That means they are more susceptible to predation because of exposure and energy loss.

Thanks for the post. Got me fired up. :)