Maple Leaf Miners: Canopy Data

by Carl Strang

Last week I returned to Maple Grove and Meacham Grove Forest Preserves to collect leaf miner data from fallen sugar maple/black maple leaves. Fallen leaves mainly represent what happened in the canopy, and data from them allow me to make comparisons between preserves, between years, and between the understory and the canopy (I had collected understory data earlier in the season).

This year all the leaves had fallen by the time I did the survey.

It was a pleasant day, and I dressed warmly enough that the November weather was no distraction.

In fact, a number of male linden looper moths were flying at Maple Grove. Also known as winter moths, they wait until November to seek mates.

Though the main purpose of the venture was to count leaf mines, I also kept my eyes and ears open for anything else of interest.

I don’t remember noticing this small concrete foundation at Maple Grove before now. It appears to be an old latrine site.

With the leaves largely changed from yellow to brown, leaf mines were easy to see.

Typical leaf litter scene.

I counted 30 leaves at each of 10 randomly selected points on each preserve. Comparisons between canopy and understory counts this year revealed no statistically significant differences at either preserve, except that there were more Phyllonorycter clemensella tent mines in the Maple Grove understory than in the canopy. This species seems more tied to the understory, and seems to be more affected by controlled fall burns of leaf litter. There were no successful burns at either preserve last year, and I suspect that accounts for the statistically significant increase in this species in the understory at Meacham Grove this year. There were no differences between 2010 and 2011 in the canopy for any of the four mine types at either preserve, and there were no differences between the preserves in canopy counts.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: