June 2021 Species Spotlight: the Native Black Legged Tick and the Invasive Yellow Flag Iris

June 23, 2021

By Robin Kuehn


The Native Black Legged Tick

Black legged tick by allysonv, some rights reserved

Black legged tick by allysonv, some rights reserved


For many of us, just thinking about the word “ticks” has us itching with that creepy crawly feeling. And for good reason! Our region is known for the prevalence of ticks such as this month’s native species, the Black-Legged, or “Deer” tick, Ixodes scapularis. While the appearance of this tick depends on the sex, life stage, and how fed it is, it can be distinguished from the other ticks found in NYS – the Deer Tick and the Lonestar Tick – by the characteristic dark legs and center. While all of these ticks can bite and potentially transmit disease, Black-legged Ticks are the sole vector for Lyme Disease. They can also spread Anaplasmosis, Babesiosis, Bartonellosis, and Borrelia miyamotoi, so knowing how to prevent bites from these ticks is crucial to healthy living in the northeast.

But first, know thy enemy. Among the ticks we were all trying to avoid last summer and fall were ravenous females, needing a blood meal to provide nutrients to her offspring. The females that fed well were able to lay their eggs this spring, and those teeny baby ticks, known as larvae, will be hatching now just in time for summer! The ravenous newborn larvae grab on to whatever warm-blooded animal happens by, especially white-footed mice and other small mammals. After 3-5 days of pigging out, the larvae drop to the ground and spend the rest of the year preparing for their over-winter transformation. The following May, they molt into nymphs, and find a new host. These nymphs are especially important to avoid because at this point they may be carrying Lyme bacteria, AND they are incredibly difficult to see because they are still roughly the size of a poppy seed. After feeding on a few more hosts, the nymphs molt into adults, which are about the size of a sesame seed. Generally at this point the females are the only ones looking for another meal, for these adult ticks only live to procreate. 

The Black-Legged Tick has been thriving along with the booming populations of host animals, including mice and white-tailed deer. With warmer winters and freezing temperatures that begin later in the season, more ticks have been found for more of the year. The CDC website shares the estimate that roughly 476,000 Americans are diagnosed and treated for Lyme Disease each year, so now is the time to practice checking for ticks and catching them before they have the chance to bite you, your family or your pets. Thorough checking is the best method, but to curtail ticks’ access to your skin, you can tuck your pant legs into your socks and tape the seam. Wearing light clothing will make it easier to spot the ticks. When you get home, throw your clothes into the dryer on high heat for 10 minutes to kill any that are hiding on the fabric. And while you wait for your clothes, check ,check, check!

Tick Sizes

Tick Sizes from CDC

For the CDC’s specific guidelines on preventing tick bites, look here:


Other resources:








The Invasive Yellow Flag Iris 

Yellow Iris, photo by jerubbo

Yellow Iris, photo by jerubbo

Who doesn’t love a showy, easily-grown, vibrantly-colored flower? Irises are named after the Greek god of rainbows, and iris flowers can certainly be hues all across the color spectrum. The wetland invader to keep your eyes out for during the very beginning of summer are Yellow Iris or Yellow Flag Irises, Iris pseudacorus. Just as showy and vibrant as its native blue cousin, the Yellow Iris thrives in wet environments and can tolerate water with a high level of acidity, like would be found in many bogs across the northeastern United States. 

Unfortunately for the inhabitants of those bogs and other local wetlands, the Yellow Iris is prolific at expanding and taking over. This species of Iris was originally native to Europe, Asia and Northern Africa. It was introduced to the United States as an ornamental in the 1700s, and then intentionally planted for use in erosion control and in water treatment ponds across the country. It does a great job holding soil in wet areas because the roots spread into a dense mat, keeping everything stable AND preventing the growth of almost any other plant. This tends to crowd out important native species like Cattails and our native Blue Flag Iris, Iris versicolor, while also reducing habitat for wetland fish and invertebrates. Additionally, the dense roots can trap sediments in streams and creeks, causing the waterway to narrow. And unfortunately for both livestock and wildlife, the plants are toxic and can’t be eaten. 

Managing this invasive species can be extremely tricky. Not only does it expand through its rhizomes, but pieces of those roots can break off and be spread by flowing water. Of course, once the aforementioned showy flowers have been pollinated, this plant creates hundreds of seeds. The seeds are enclosed in a pod with an airspace that acts as a flotation device, so the flow of the waterway can carry the Yellow Iris offspring along to new locations. The only way to effectively manage this plant is to dig out every last root before it can go to seed, or to cut it repeatedly through the whole season, and this has to be done carefully because the sap can cause skin irritation. 

Yellow Irises by Rosalie Oceanna-Kolb

Yellow Irises by Rosalie Oceanna-Kolb

If you’re out on a stroll along a stream or pond and spot this bright yellow trilaterally-symmetric flower, post a picture to iNaturalist.org or to nyimapinvasives.org! The more we report the places it has taken root, the better it can be managed by experts in organizations like the Lower Hudson PRISM Invasives Strikeforce, and other land stewards. If you see it while hiking on the Wallkill Valley Rail Trail or in the Nyquist-Harcourt Wildlife Sanctuary, be sure to post it on iNaturalist so we can find it for future invasive species management programs!