Aphid

5837   Good evening.  Found hundreds of these crawling on our back yard fence.  Calgary, Alberta.   Found today.  Yard has loads of vegetation.   The bug is very small, maybe 1/8 to ¼ inch, body is all black.   Rob

Like No. 5832, this is an aphid (Hemiptera/Sternorrhyncha: Aphididae). All aphids are obligatory sap feeders, and in addition to any harm they may cause plants, they can be real nuisances as well from other standpoints. See http://tinyurl.com/jexmcaefor more detailed information. Ed Saugstad, retired entomologist; Sinks Grove, WV