Skip Maine state header navigation
Skip First Level Navigation | Skip All Navigation
|Home | Contact Us|
Home > Elongate hemlock scale, Fiorinia externa
Alternate name: Fiorinia scale, Abbreviated Name: EHS
Hosts: Hemlock, fir = primary hosts. Spruce is also a common host. Secondary coniferous hosts only usually infested in the presence of heavy scale populations on primary hosts. Pines not affected.
Distribution in US: South to Georgia and South Carolina, west to Ohio, Michigan and Minnesota and, north to southern New York and New England (including southern NH and ME).
Known populations in Maine: map
Where to look: Planted hemlock, fir and spruce. Planted and natural hemlock in areas affected by hemlock woolly adelgid or near detections of elongate hemlock scale.
Field Characteristics (See Photos Below): Yellow spots on foliage apparent on the upper surfaces of the needles. Foliage of more heavily infested trees will have a dirty appearance from a distance. Crowns may be thin. Female scales are covered by a parallel-sided, yellowish-brown waxy coating. Males, by a white, elongate coating. Crawlers and adult males are tiny, yellow, translucent and soft bodied. Crawlers are present during the warmer months of the year. Presence of crawlers and winged males can be determined by jarring infested foliage over a piece of petroleum jelly coated dark paper.
NOTE: In 2009, 2010 and 2011 detections of elongate hemlock scale have been reported during the last week of August. The insect may be more noticeable at that time due to the length of time it has been feeding over the course of the growing season. It appears to be a good time of year to check your trees for this pest.
Waxy Buildup Apparent from a Distance in Late Summer/Early Fall (pictured below on fir)
Photos: More photos can be found at: http://www.invasive.org/browse/subthumb.cfm?sub=304.
Elongate hemlock scale on hemlock needles:
Elongate hemlock scale on hemlock (left, middle (adelgid circled)) and fir (right):
Needle discoloration on hemlock (left) and fir (right):
Crawlers (left) and adult males (right, only winged form):
Crawlers (~0.1 to 0.2 mm)
Modified: November 13, 2012
|Copyright © 2005 All rights reserved.|