Invasive SpeciesEurasian watermilfoil

Myriophyllum spicatum
NOT FOUND by kchambers
Norway, ME
ID Confirmed
Quality checked by kchambers
Peer reviewed by
Field Notes
We are happy because it's about to rain, and we get to go swimming later. This pond is at the Roberts Farm Land Preserve. It once had a dam and was a source of water for the farm. It is now surrounded by woods. We can hear frogs in the pond and can see the ripples in the water. There is a duck in the pond, and a lot of grass growing out of the water. We are excited to collect our data and go catch frogs.
Supporting Evidence
Photo of my evidence.
The stem is green. It is not reddish, brown, or pinkish white.
Photo of my evidence.
The plant is the submerged one in the front of this picture. It is July, and there are no flower spikes rising above the water.
Photo of my evidence.
The leaf arrangement is alternating, not whorled.
Species Observation: Species Looked For
Did you find it?: 
I think I did not find it
Scientific name:
Myriophyllum spicatum
Common name:
Eurasian watermilfoil
Sampling method: 
Weed weasel
Photo of our sampling method.
Place Studied
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Map this species
N 44.209190 °
W -70.569560 °
Observation Site Information
A photo of our study site.
Freshwater - In a pond or lake
Trip Information
Roberts Farm Pond
Trip date: 
Wed, 2012-07-18 09:00
Town or city: 
Norway, ME
Type of investigation: 
Species Survey
Lower Androscoggin
MIDAS Code: 



Thank you for sending in the specimen! Once we were able to see the plant up close and "in person", it became obvious that YOU WERE ABSOLUTELY RIGHT; it is NOT a milfoil. What appear in the photo to be feather-divided leaves are not true feather divided leaves. On a "true" feather divided leaf, the leaflets that occur in pairs up each side of the central midrib are single hair-like strands. Some of the leaflets on the plant you found in Robert's Farm Pond are NOT single hairlike strands, they are forked or barbed. Also, as you noted, the alternate leaf arrangement is fairly consistent all the way up the stem.

You found mermaid weed, a native plant that is not very common in Maine. Excellent work!

Phew, not invasive milfoil!

This is such a cool way to connect and share information online and by snail mail. I like it a lot.

I'm actually taking students to Roberts Farm tomorrow on a field trip. I will bring my weed weasel and have students try and get a sample. How would you like me to get ahold of you?

Hi Kristin! I tried writing directly to your school email over the weekend, but have not heard back from you so also posting here.

Thanks so much for the prompt reply. I was out of email contact yesterday and it looks like I missed your Thursday evening message. Were you able to collect a specimen yesterday? If so, it would be great if you could send it to us ASAP. Is the Post Office closed on Monday? I'm not sure. If so, Tuesday's mail would be fine. Between now and when you ship the specimen, you can keep it fresh in a jar of water in your fridge.

To ship, place the specimen, damp—not wet, in a Ziploc plastic bag and then in a USPS Priority Mail box. Please download our tracking form our website, fill out the relevant portions, and include that in the box.

We’ll be on the lookout for your specimen and will get back to you right away with our findings.

Thank you again for keeping an eye on the plants.

All the best.


Right again! This is NOT Eurasian water-milfoil. It IS, however,a milfoil, and it is important to remember that there are THREE invasive milfoils on Maine's "unwanted" list. Two of these invasive milfoils--Eurasian milfoil and parrot feather--can confidently be ruled out from these photos. The leaves of both, are as you suggest, are almost always strictly whorled with noticeable open space between each whorl.

Ruling out the third invasive milfoil--variable water-milfoil--however, is not quite as easy from these photos. Occasional "offsetting" of the whorls (leaves not meeting up precisely at the stem like spokes on a wheel, but instead appearing as alternate) is not uncommon with this species. Other features such as stem color, space between whorls, whorl diameter, etc. may also be quite variable. In keeping with its common name, variable milfoil displays a wide range of vegetative VARIABILITY. So, unfortunately, though I do not highly suspect variable milfoil in this case, I also cannot rule it out.

For future reference here is the 'rule of thumb' we teach our volunteer Invasive Plant Patrollers . . . IF you find a submersed aquatic plant with true feather-divided leaves arranged on stems, it IS a milfoil. ALL milfoils are suspicious until proven otherwise. Sometimes a photo is adequate for identifying a milfoil to species, but often it is not. If you do find a milfoil, it is ALWAYS best to err on the side of caution. Collect a specimen, keep it in a ziploc bag or jar with some water, and call us here at the VLMP. If we cannot help you identify the milfoil from your description and photos, we will tell you how to ship your specimen to us so we can take a closer look at it. If WE cannot identify it, we will send it out for DNA analysis. The DNA will tell us with certainty which species of milfoil you have found.

To be on the safe side, we will contact our friends at Robert's Farm Preserve and do our best to obtain a specimen from your study location. We'll keep you posted on our findings.

Thanks again for your keen observations. You are obviously very good at this! We hope you will keep hunting for aquatic invaders, and that you NEVER find what you are looking for! :) R

You guys did a really nice job looking closely and ruling out invasive milfoil. At first glace at your photos, the feather divided leaves looked whorled. Thanks for pointing out that they are alternate! Nicely done.

I hope you found all kinds of frogs.