Oak Tree

An Oak

One of my goals for this year is to become acquainted with the various trees of Illinois. Often the species of tree is significant when it comes to identifying other organisms, such as insects or fungi. Knowing that a particular mushroom usually grows in the vicinity of a certain tree, for example, can help in locating said mushroom. After all, trees are usually much bigger than mushrooms and easier to spot from a far.  On my trip to the Isle a La Cache Forest Preserve, I took a photo of the tree opposite. I recognized it as an oak, because you know, it has leaves that look like oak leaves. What species, however, I had no clue.  

Oak leaves.

Of the roughly 600 species of oak, there about about 52 that are native to the United States, and 20 to Illinois. The latter group are: bur oak, chestnut oak, chinkapin oak, overcup oak, post oak, swamp chestnut oak, swamp white oak, white oak, black oak, blackjack oak, cherrybark oak, northern pin oak, northern red oak, nuttall oak, pin oak, scarlet oak, shingle oak, shumard oak, southern red oak, and willow oak. 

Tree Bark. Woof, woof.

So, if I fake expertise and take a wild guess, then I have roughly a 5% chance of getting it right. Sadly, that  means I have a 95% chance a being corrected when confronted with someone who actually knows what he is talking about. I don't like those odds.

Fortunately, we can improve things by knowing a few facts about each each species. Hill's oak (Quercus ellipsoida), for example, is usually only found in the northern counties, whereas Spanish oak (Quercus falcata), Rock Chestnut Oak (Quercus montana), and Southern Red Oak (Quercus falcata) in the south. Or better yet, you just memorized the characteristics  specific to each tree. Imagine that!

My first assumption upon seeing the deep grooves of the bark was that this was a Bur oak (Quercus macrocarpa), yet the leaves do not have the deep sinuses typical of the tree. Another oak that has deep fissures is the swamp white oak (Quercus bicolor), which fits nicely into fact that the tree is situated in a flood plane. The colour of bark is grayish, the leaves wider at tip than at the base, and the lobes are not pointed. All these facts suggest that this is indeed the swamp white oak. 

Isle a la Cache

For the past five years on my commute to and from work, I have driven over small island situated in the Des Plaines river known as the Isle a La Cache. If you aren't familiar with the area, it can be easy to miss that fact that you just crossed an island. A busy dual lane road dissects the island in two, and to the east are two large industrial plants - one an oil refinery and the other electrical power plant. 

The island is owned by the Will County Forest Preserve and houses a museum that portrays the life of Native American tribes, as well as the first explorers to the area. The story goes that in the 17th century a French trader, when warned of possible danger further down the river, buried his cache of goods on the island. Hence the name.

The pond that geese patrol

So on my way home from work, I decided to finally stop and explore the island, or at least the southern section. The museum was about to close, so I settled for just a quick stroll. Behind the museum was a pond occupied by a lone male mallard duck. He was a little camera shy, and took flight before I could ask him to say cheese. The  opposite side of the pond was patrolled by a squadron of geese, of the Canadian persuasion. I decided to stay clear of them. I don't trust geese. Or Canadians.

Where water be rushed

I left the safety of the paved path and followed the trail into the woods, towards the sound of rushing water. The area is quite picturesque, and you quickly forget that you are surrounded by industry and its large polluting chimney stacks. 

Where no man treadeth

One of the things I know about the island is that during heavy rains, the Des Plaines river is prone to flooding. There have been times when the northern part of the island is totally submerged by a feet or two of water, which then overflows onto the road. The southern part seems to fair a little better, but it's not unusual to see picnic benches in the middle of a shallow swimming pool.  

I stopped several times on the trail to snap photos of the river and any wildflowers I saw. There wasn't much, and what I did see was mostly the ever invasive garlic mustard, Alliaria petiolata. Oddly enough, this was one plant I recalled from my naturalist childhood, and could name it straight away (although I did verify I was correct). I remember how I looked it up in the one book I had on British plants, mainly because it looked similar to the unrelated stinging nettle. I also knew from literature that garlic mustard is not welcome in restored prairie habitats, and that volunteers are often recruited with one agenda - to seek and destroy this plant. 

No hope.

Phlox divaricata

Having accidentally strayed off the trail, my eye was caught by one cute little lavender flower screaming to be noticed. Being such an amateur botanist, I had no idea what it was. I took a photo, and later identified it as wild phlox, Phlox divaricata. I would see this little fellow again. 

Besides a passing red admiral butterfly, there was no other wildlife I could positively identify. For a brief second, I would occasionally see something swimming in the river, and then it would be gone again. I was pestered by a unknown fly or two, and spared a thought for a tree that appeared to have fallen victim to a beaver, or renegade forest ranger. Or maybe both. I did photograph oak tree in the hope of naming it. Oaks and maples - those of the two genera of trees I want to be able to differentiate between species.