Sharing Biology Class: Part II The Galls

 It's time for the second round of the Biology Class series!

This lab that my class and I did last fall had to do with a certain natural phenomenons called "galls."

What are galls you ask?

Galls are those swelled, green balls found on Goldenrod stems. For class the friday before lab that week, our homework was to go out and collect galls. They are most usually found in the giant gatherings of goldenrod (not on singular stalks in the middle of nowhere) and our job was to grab 'em, tag 'em and bag 'em. ....Ok, so tagging didn't happen but all of us brought in twenty or so galls that Monday morning for dissection.

Dissection you say? The whole reason that these galls are in existence is because of the parasitic Gall Fly and Gall Moth. These two insects spend their larval stage inside the galls. Eggs are laid inside the stem, and the gall forms as the eggs grow into maggots. The white plant tissue surrounding the maggot's little hideout serves as it's nutrition and protection (although one type of beetle can sometimes burrow into a gall and feast on the white grub within). Eventually, the maggots mature and emerge from the gall as adults to start the cycle all over.

Anyway, back to dissection. Our job was to take scalpels and cut open those galls. It was a relatively fun class, interuppted here and there by occational cheers along the lines of "Hey guys! I DIDN'T accidently cut through my grub this time!"  We basically had to measure the galls, count the ones that had maggots in them, and examine the inside nutritional tissue.

All in all, galls are pretty cool. The grubs aren't slimy and discusting (they're more like really, really short white earthworms) and I was happy to finally learn what the heck those swollen lumps were on the flowers.

** Thanks to http://www.gpnc.org/goldenro.htm and http://www.fcps.edu/islandcreekes/ecology/goldenrod_gall_fly.htm for helping me remember some information!