Natural History Ch. 16- Invasive Species in the Smokies

how many invasive species are in the park?

400 plus

how many species have spread aggressively and caused widespread ecosystem damage or alteration?

60

what is the number one invasive species?

humans

how many people visit the smokies each year?

12-14 million

what do humans bring in?

foreign plants, animals, waste, disease, trash, and physical damage

how many million visit cades cove?

2 mil

what does vehicle exhaust do?

pollutes the air

what do humans approaching/feeding wildlife do?

affect their behavior, induce stress, and disrupt natural cycles

explain balsam wooly adelgid

Adelges picaea – was introduced to NA in 1908

First seen in smokies in 1963

Has killed whole stands of Fraser fir in the spruce-fir zones.

Adelgid covers itself with wooly wax as it feeds on the tree by injecting saliva. Saliva contains toxins that affect cell growth

how do frasier firs die from wooly adelgid?

Fraser firs over-react, clogging transport tissues and literally starve themselves to death.

Nearly 90% of Fraser firs in the park have already succumbed to this insect

what was the american chestnut like?

once the dominant deciduous tree in the eastern United States. It was as common as oaks and maples.25% of all eastern woodlands were composed of this tree species and made up approximately 40-45% of the canopy. 1 our of 4 trees in the smokies. The largest trees had trunk diameters of up to 10 feet and could live for over 400 years.

what was unique about the american chestnut?

it blooms in june which prevented late frosts from killing flowering and seed production. Oaks and hickories, two important mast replacement trees, bloom in March and April, making them susceptible to frost damage. With the loss of the American Chestnut, a dependable food source for the entire eastern forest habitat no longer exists.

why was the american chestnut the best timber tree?

straight growth, tight grain, and resistance to rot

when was the parasitic fungus accidentally introducted?

late 1800s and in 1905, it was identified in New York City and began moving rapidly through the eastern forests.

how does the fungus kill the tree

enters the tree through any type of fresh injury in the tree's bark and spreads throughout the vascular tissues. Eventually, the flow of nutrients is cut off and the tree starves to death.

what were the stats of the american chestnut by the 1950s?

99.9% of the trees in the east were dead (5.5 billion trees)

what was the failed blight stop?

Attempt to stop the blight was done in Pennsylvania, where a massive "firebreak" of felled chestnuts (30,000+) was attempted. It ultimately failed.

how are chestnuts evolutionarily stuck?

The blight does not affect the root systems, so trees continue to push up sprouts from roots. Some live long enough to produce a few seeds but they don't reach sexual maturity

where were a few flowering chestnuts found?

andrews bald

explain the MC Chestnut Orchard

First planted in Spring of 2018

Approximately 6000 seeds have been planted

80+% of seeds have germinated into trees.

In the last two years we have begun removing dead trees and infected trees that show no hope of survival

As of this past Saturday (November 22), two genetic families are showing real promise at resisting the blight. Our orchard has been described as

"the best seed orchard in the

southeastern United States" by the American Chestnut Foundation.

where and when was dogwood anthracnose introduced?

introduced to the United States in the 1970s.

Arrived in Maryland in 1983 and Georgia in 1987.

Began affecting park around 1989.

what is the kill rate of anthracnose?

90%

what has been utilized to keep the dogwood anthracnose in check?

prescribed fires

what can cause the outbreak of dogwood anthracnose?

Cool, wet springs cause outbreaks of the disease whcih can affect flowering, which reduces the production of the high protein berries for birds and other wildlife.

how much food do dogwood trees produce?

10 kg ecah each

what do dogwood trees reduce?

soil calcium because the leaves of the dogwood have highest content of any eastern tree.

explain how the gypsy moth got introduced

In 1869, gypsy moth larvae from France were being evaluated in a lab in Massachucets. The were sitting on a window sill and were blown out into the environment.

By 1987 it had established itself in North America.

what are the effects and effort on the gypsy moth?

It is a widespread and damaging insect across the continent. It defoliates trees (300 different species), particularly oaks.

Early trapping efforts have proven effective in preventing the spread of gyspy moth in the park, as well as native organisms (birds) beginning to feed on the caterpillar stage of the invasive.

explain beech bark disease

an insect and the nectria fungus cause this disease. First recorded in park in 1993.

Killed large %s of high elevation beech trees and is now moving to lower elevation trees. The disease initially had a huge impact in the park, but regular monitoring has helped regulate the impact.

how does hemlock woolly adelgid live?

first arrived in 2001 and has had a massive impact on Hemlock stands.

Insects are the size of a pinhead, they are named for the fuzzy white appearance found on the underside of the branches of hemlock trees.

Nymphs go through 4 stages before becoming adults. Each adult can produce up to 500 eggs. Native to Asia, arrived in the park in approximately 2002.

how did hemlock woolly adelgid effect the smokies?

GSM has the largest expanse of hemlock forests in the eastern United States.

Insecticide imidacloprid has been shown to be highly effective against the insect, but each treatment only lasts 5-7 years. All trail side, developed, and roadside trees that could be treated have been treated so far.

There are nearly 800 acres of old growth hemlock, 18,000 acres of mature hemlock.

Over 280,000 trees have been chemically treated against the adelgid using imidacloprid.

what is the biotic control of HWA?

In 2007 a non-native ladybird beetle was introduced (native predator that feeds on adelgid). In 2006 a different predatory beetle was released. in 2013 a new beetle that is more voracious and withstood cold better was introduced. As of 2021, nearly 610,000 beetles of the Laricobius genus have been released and are showing clear signs of successfully impacting the Adelgid

how does the mandate of the NP related to invasive species?

managing invasive species is one of the most important tasks of the National Park Service to ensure the health and wellbeing of these natural areas