Insects and animals visit our outdoor spaces all the time, even though we may not see them. Some are nocturnal being active at night when we are not typically in our yards or gardens. They do leave signs they were there though. Some leave tracks where they were walking or crawling about, others leave feeding marks where they had a meal. Take some time to observe the living beings sharing your outdoor areas.
Elm trees can be attacked by an Elm Bark Beetle, which feeds just under the bark in the cambium layer of the tree. The tiny insect feeds by chewing up the moist plant tissue, leaving a beautiful and distinctive pattern once the bark dies and falls off as shown in the photo below. The elm bark beetle are known to spread Dutch Elm Disease to elm trees in the process of feeding.


Adult European elm bark beetle. Credit: J. Benzel, Screening Aids,
USDA APHIS ITP, Bugwood.org
A newer pest in the northeast which also feeds just under the bark is the Emerald Ash Borer. It is emerald green as its common name implies, and also small in size at less than a half inch. Control is very difficult since the larval stage feeds underneath the bark where contact insecticides cannot reach. The adult beetles feed on the leaves in spring after they emerge from D-shaped exit holes they make in the bark when they chew their way out of the tree. It leaves a more random and larger feeding pattern, with the ability to kill an ash tree in three years.


Emerald Ash Borer Adult, Photo by David Cappaert, Bugwood.org
A group of insects aptly named leafminers feed in between the top and bottom layers of a leaf. You can see the feeding trails left by the larval stage of some moths, sawflies and flies. They are usually host specific, each species of insect feeding on only one species of plant. Once again, pesticides will not reach the inside of the leaf where the insect is located. Remove and destroy infected leaves to kill the leafminer.
Swiss chard leafminer tunnels

Boxwood leafminer, topside of leaf.

The next photo of a pattern on a pipe of a gate near a lake was sent to our office asking what made the etching. The marks are feeding trails of snails eating the algae growing on the pipe in the wetland area. Snails have a ribbon-like tongue called a radula which has thousands of tiny teeth that line the surface used to rasp up the algae.

Woodpeckers leave their marks while pecking on trees. They peck to make noise to find a mate or declare their staked out territory. They also peck into trees in search of insects to eat. The red-bellied sapsucker makes small holes in a pegboard fashion as it systematically covers an area of a tree to seek out every insect.

magazine.uconn.edu/2017/09/26/flocking-to-storrs/
Of course many animals leave tracks in the snow and soil, like hoofed deer and the three toed turkeys. Below are vole tracks meandering around its tunnel opening.

What tracks can you find?
-Carol Quish