ELONGATE HEMLOCK SCALE
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 (PDF | 2.64 MB)
To date forest infestations of elongate hemlock scale in Maine have only been found in Kittery Point. Infestations on planted trees have been found from Kittery to Mount Desert. It is probable that elongate hemlock scale is established in the Maine's forests outside of Kittery.
County Town No. Sites Host Detection Year York Kittery 2 Hemlock 2010, 2012
County Town No. Sites Host Detection Year Cumberland Cape Elizabeth 1 Hemlock/Fir 2010 Falmouth 1 Fir 2012 Frye Island 1 Hemlock 2016 Gorham 1 Fir 2011 Portland 1 Hemlock 2011 Scarborough 1 Fir 2011 Yarmouth 1 Hemlock 2012 Hancock Sedgwick 1 Hemlock 2012 Mount Desert 1 Hemlock/Fir 2012 Sagadahoc Topsham 1 Fir 2012 York Berwick 1 Fir 2011 Kennebunk 1 Hemlock/Fir 2009 Kennebunkport 1 Hemlock 2009 Old Orchard Beach 1 Hemlock 2010 Saco 1 Fir 2012 Wells 1 Hemlock 2011 York 3 Hemlock (1)/Fir (2) 2011, 2012
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, 2011, and 2016 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):
Note: other pathogens, pests and processes will cause needle yellowing. Look for scale coverings on the needle undersides if yellowing is apparent on the upper surfaces of the needles.
Crawlers (left) and adult males (right, only winged form):
Note: The insects pictured below are trapped in petroleum jelly.
Crawlers (~0.1 to 0.2 mm)
Modified: November 13, 2012