Transcript Native Range

Hemlock Wolly
Adelgid.(HWA)
Hemlock Tree Loss
By : Landon Warren
What are Hemlock Trees?

The hemlock tree is of course a tree, that is evergreen(which means it is
always green). It typically grows 40 to 70 feet tall with a slender trunk and a
narrow crown of slightly drooping branches.

Scientific Name: Tsuga caroliniana

Common Name: Carolina Hemlock

Plant Type: Mid-size evergreen coniferous tree

Height: 40 to 70 feet

Cultivation Zones: 5 - 8

Native Habitat: Mountain slopes and ridges in mixed forests

Native Range: Mid elevations of the southern Appalachian mountains. See
distribution map below.
Distribution Map
Range Map Source:
reasons hemlock trees are important

Normally, hemlock trees grow beside rivers and creeks so they shade the
water and regulate the water temperature for fishes and other animals that
live in water. Without the hemlock trees, the fish and other animals that live
in the water will die out because the hemlock trees regulated the water to
the right temperature for these animals. Most fish that live in streams
require, cold, clear water to survive. Also we need to help hemlock trees
because they are subline.
Other reasons why are hemlock trees so
important???
They are a keystone species
We can never replace hemlock trees ,
We don’t have any species that can
fill in the hemlock trees place.
A bird feeds on this tree and without
the tree , the bird will die out.
What is happening to the hemlock trees?
There is a tiny species called the Hemlock Woolly Adelgid that feeds on hemlock
trees and kills them. It can destroy the hemlock tree and make it go extinct .
People wish that hemlock trees are placid. So with your help we could keep
hemlock trees exquisite!!
What are possible solution's to the
HWA???

A long term solution is the introduction of predatory insects from the native range
of HWA. Lari beetles have been released throughout the Southern
Appalachians. Other beetles have also been released. This approach is called
biological control, where one species interacts with another species. In this case
because HWA is not native to our area there are no native species present to keep
the species in check, and so the end result is explosive growth of
HWA. Entomologists studied HWA in it's native range (east Asia) with the goal of
finding other species that interact with HWA. One of these species the Lari
beetles (Laricobius nigrinus). L. nigrinus is not native to our area. So, you might
question the wisdom of introducing another non-native species in order to control
a non-native species. In the past this biological control approach, while sound in
principle, has backfired. The intentionally released non-native species didn't do
what it was supposed to do and created another problem. Learning from these
past mistakes, entomologists carefully studied these Lari beetles and found that
they only feed on HWA and nothing else. So, I am optimistic that this approach
will work this time. Of course, ecological systems are very complex and it is
possible that there will be some unintended consequences, but we haven't seen
that happen yet.
The effect of not having hemlock trees.
Not having hemlock trees will have a large effect on people AND animals.
In the future if the hemlock wooly aldelgid keeps on feeding on it, the hemlock
trees will die out and the water will get too hot and kill the animals that live in
the river.
Is it possible can hemlock trees abate???

Yes it is possible hemlock trees can abate,but with our help, it will not abate.
With your help,we can save the hemlock trees but if they die out , I will be
very melancholy.
Hemlock
maps
Any Questions???
?????
Thank you