Golden Protector

landin_marigold_web

I’ve always planted marigolds among my garden. I’ve heard these orange beauties have protective properties against herbivores. Is it true?

Hmm. Most researchers have found properties released from marigold roots inhibit bacteria, fungi, and/or nematodes (although this is extremely variable, depending upon the part of the plant used, how the marigolds are grown, and the pest species tested).

Most interesting sidetrack from my search… some research shows inhibition of Plasmodium, the microscopic organism that causes malaria (1).

Thanks to Charlie O’Shields of DoodleWash for the #WorldWatercolorMonth inspiration.

  1. Pankaj Gupta & Neeru Vasudeva (2010) In vitro antiplasmodial and antimicrobial potential of Tagetes erecta roots, Pharmaceutical Biology, 48:11, 1218-1223
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Oak Scale – Sitting There Like a Tiny Bump on a Log

OakScaleSee that tiny bump on the branch? You’re looking at a mom protecting hundreds of babies. Well, actually, the mama Oak Scale insect (Parthenolecanium quercifex) is dead now, but her exoskeleton is still harboring those little eggs underneath. When those baby Scales hatch around the end of May, the tiny darlings will move out to the oak leaves and begin to SUCK THAT POOR TREE DRY. They sniff out the precious sugar-water flowing through veins in leaves, insert their straw-like mouth parts and drink up. As the year progresses, Scales grow and mate. Mama lays her eggs beneath her and dies, making way for next May’s new generation.
scaleEggs(These are the eggs… um, on my kitchen table. Didn’t realize they’d pop out like that when I lifted the mama Scale off. Oops.)

In the insect’s defense, healthy trees can resist Scale infestations. Some leaves and twigs may fall off – that’s all. But trees that are weakened (by physical damage, drought, chemicals, etc.) can be killed by the insects.

Cool Climate Change research recently found that densities of Oak Scale are up to 13x higher in warm urban areas! (1) Since things are getting toastier here on Earth, we may want to get more familiar with the life & times of the Oak Scale.

1. Meineke EK, Dunn RR, Sexton JO, Frank SD (2013) Urban Warming Drives Insect Pest Abundance on Street Trees. PLoS ONE 8(3): e59687. doi:10.1371/journal.pone.0059687

Invasion of the House Finch

HouseFinch_JML

Once upon a time, House Finches (Haemorhous mexicanus) only lived west of the Rocky Mountains. Then, in 1940, a group of captive birds flew to freedom from their New York cages. Their numbers slowly grew until… BOOM… population explosion. Today, House Finches reside throughout the U.S. and Mexico.

There’s a downside to dense populations though – disease. In the 1990s, a bacterium (Mycoplasma gallisepticum) started swirling among groups of House Finches. The infection causes conjunctivitis (like “pinkeye”) in the birds. If you’re a bird with swollen eyelids and crusty build up, you’re not going to be very good at flying or avoiding the neighbor’s cat.

Today, roughly half as many House Finches live in the East compared to 20 years ago.


If you’d like to learn more about House Finch diseases (with gross pictures), visit http://www.birds.cornell.edu/hofi/abtdisease.html.

And if you’d like to see the growth and decline of House Finch populations in your state, check out www.pwrc.usgs.gov/BBS/RawData/ (1)- fun with data!.

1. Pardieck, K.L., D.J. Ziolkowski Jr., M.-A.R. Hudson. 2014. North American Breeding Bird Survey Dataset 1966 – 2013, version 2013.0. U.S. Geological Survey, Patuxent Wildlife Research Center.