A simple definition of pollution is the introduction of harmful materials into the environment. These harmful materials are called pollutants. Pollutants can be natural, such as volcanic ash. They can also be created by human activity, such as trash or runoff produced by factories. Pollutants damage the quality of air, water, and land. Sometimes you can see pollution like trash on the ground or the haze in the air over downtown. Sometimes you can smell pollution like the nasty odors that emanate from our local water treatment plant. Sometimes you can hear pollution like the traffic on W 11th Street or even distant sirens going by. And, a lot of times, you can’t see, smell, hear, or feel pollution. But, it’s still there.

Amazingly, trees are able to clean the air and absorb harmful airborne particles and gaseous pollutants such as nitrogen oxides, ammonia and sulfur dioxide through their leaves, bark and roots. This improves the air quality in the microclimate around the trees and contributes to a healthier and cleaner environment overall. Ground-level ozone formation is reduced because air temperatures in tree-filled areas are cooler. Trees also soak up the harmful carbon dioxide in our atmosphere. In one year, an acre of mature trees absorbs the same volume of carbon monoxide as produced from a 26,000 mile car journey! Aside from cleaning the air for us, trees supply us with fresh oxygen to breathe. 

There are other plants in this forest that are quite resilient in the face of pollution, too. As you look at the bark of the trunk of this tree, you can see light patches on it. Lichen have about 15,000 species of plantlike organisms that consist of a symbiotic association of algae or cyanobacteria and fungi. They colonize on the tree bark. They also colonize on exposed rock and can be found as part of biological soil crust. Normally, lichen grow outward from the tree bark. But, here in our forest, because of the canopy cover and the unseen pollution in the air, the lichen grow so flat they almost look two dimensional or like they are an actual part of the bark instead of a colony on top of the bark.

Sometimes as you walk through different parts of our forest, you might detect different odors. Those odors are proof that there is pollution in the air nearby. Even though you aren’t seeing it, you are smelling it.

Another harmful pollution that we often smell and then find in our forest is dog feces. Dog feces can carry worms and protozoa as well as fecal coliform bacteria. Fecal coliform bacteria is the group of bacteria which includes E. coli which can cause cramps, diarrhea, serious intestinal and kidney illness and even death to people who ingest contaminated water.

Parvovirus is highly contagious to other dogs, resistant to many disinfectants, is both extremely hardy and capable of surviving in the environment for up to two years.

People often think that dog feces will just go away on its own or fertilize the area around it. However, rain will wash the feces down storm drains and into waterways like rivers, bays, and beaches. People might get sick from other infections besides E. coli.

Pet waste is very toxic. The Environmental Protection Agency estimates that waste produced by just 100 dogs in two or three days (or one weekend) can contain enough bacteria to temporarily close a bay to swimming and shell fishing. In our forest, feces can be washed into our ephemeral ponds which our resident animals use to survive and thrive since this is their home.

So, please be kind to the environment in the forest and keep your dog on a leash and on the trails at all times. Doggie poop pick up bags are provided at frequent intervals around the forest by Friends of The Lorraine Cherry Nature Preserve. Please pick up your dog’s feces and dispose of it in the trash cans so that the animals which live here and the humans who visit will stay safe and healthy.