Thursday, September 1, 2016

Iris Eradication Efforts

 There's no question that Yellow Iris (Iris pseudoacorus) is beautiful.  I'm sure that's why it was welcomed to American gardens from its native lands overseas.  The problem is, it did not stay in those gardens, but now has spread to waterways across the U.S., threatening to supplant vast swaths of native riparian flora to form impenetrable monocultures where no other plants can grow.  By now, one of those waterways is my cherished Hudson River at Moreau, which is part of Moreau Lake State Park.  I've been paddling this section of the Hudson between the Spier Falls and Sherman Island dams for nearly 25 years, and I know the shoreline vegetation pretty much by heart.  So I was quite surprised last summer when I found two giant clumps of Yellow Iris where I had not seen them before.  The clumps occurred quite a distance apart, one in a little cove just upstream from the Sherman Island Dam (above), and the second far back in a swampy area a quarter-mile or so further upstream (below).

Of course, I tried to pull them out.  OH boy!  No such luck!  They were rooted so deep, it seemed it would take some dynamite to dislodge them.  But today I learned it just took a dynamite team of New York State Parks Invasive Species Management folks to do the job.  After I reported finding these iris clumps to Moreau Lake State Park Manager Peter Iskenderian, he arranged for this crew to eradicate them, and he asked if I could accompany the crew to show them where the iris grew.  Well, sure I could!

We were lucky we had such a beautiful day to be paddling on the river and then mucking about in the swamp.  Even though the crew had boots on, they were soon up to their knees, or higher, in muddy water as they worked to dislodge the iris.  I was lucky I got to sit in my boat while Dave, Casey, Taylor, and Mike did all the heavy digging.  NY State Parks Regional Natural Resource Steward Casey Holzworth, seen standing in the photo above, supervised the effort.

This crew member, also named Casey, managed to smile, despite the discomforts.  It was not easy to dig out those giant tuberous roots, bag all parts of the plants, and haul them away.

One clump down, we next headed downstream to take on the second one, at the back of a quiet cove.

This was one BIG clump of Yellow Iris!

By the time we were done, each canoe (we had three, including my little Hornbeck) was laden with many bags of iris leaves, roots, and the mud that they grew in.  I carried two bags, too heavy for me to lift on my own, in my own little boat.  We were lucky we had a brisk wind at our backs to push us the mile or so upstream to our landing site.

Yes, we had work to do today, but we also had many pleasures paddling this gorgeous stretch of the Hudson.  How beautiful are these vivid blue Closed Gentians?  These are just one of our native species that the Yellow Iris, left to spread, would overwhelm and supplant.  Mixed in with this cluster of Gentians are some other native flowers, including white Turtlehead blooms and the yellow-centered Beggar Ticks.

This mating pair of Autumn Meadowhawk Dragonflies found my sun-burned knee a convenient place to rest and didn't seem to mind my poking my camera lens at them.

And here was the highlight of my trip today: finding a large population of Small Floating Bladderwort (Utricularia radiata) back in the swampy area we visited first.

This little yellow flower, borne along on inflated "pontoons," is listed as a "Threatened" species in New York, but I found dozens of them floating among the Pickerelweed plants and Buttonbush shrubs.  I have found this species in abundant numbers before, but in a section of the Hudson some miles -- and two dams! -- downstream, near Glens Falls.  This is the highest upstream I have found them so far, and in waters that are within the boundaries of Moreau Lake State Park.   If those Yellow Iris had been left to spread, the Small Floating Bladderwort is just one of the native species that might have been supplanted.  So I'm very grateful to the New York State Parks Invasive Species Management team for the work they accomplished today.  Thank you,  dear folks, for protecting "my" beloved river and all the native plants that populate its banks and waters.

Postscript:  The invasive-species crew also removed a big Autumn Olive (Elaeagnus umbellata) and a small shrub I asserted was Glossy Buckthorn (Frangula alnus) from the powerline that runs just north of Mud Pond at Moreau Lake State Park.  Neither of these isolated shrubs had yet grown invasive at their sites, but left in place, they were likely to.  Good to nip these nuisances in the bud!


Anne Ford Taylor said...

I am thankful, too, for the NYS Parks Invasive Species Management folks and you for posting the wonderful pictures which I so enjoy. Keep up the good work!

threecollie said...

Wonderful what you do! I had no idea that these were considered invasive until last year. we had one in my tiny garden pond and when I decided to dispose of it the guys had to use to skid steer to get it out despite the pond only holding three hundred gallons of water!

Salty Pumpkin Studio said...

Bravo! Great work done!

I can't imagine being knee deep in that muck pulling digging and getting around. I am also thankful for the dedication of those who do the work. And I have to say, those tee shirts are neat.

Andrew Bradshaw said...

It's nice to see that some states can afford to remove invasive species. Here in Illinois, our budget crisis and prior cuts have all but eliminated state park funding.

The Furry Gnome said...

That's a new one for me, not aware of Yellow Iris being so invasive here. We have big volunteer efforts here to control Buckthorn and Garlic Mustard though.

Momo said...

Great job helping to rid the Yellow Iris!! I was there last week and enjoyed the Closed Blue Gentians and Turtleheads as well as the long lasting Cardinal Flowers. Happy Paddling and exploring!