Trees in the U.S. facing devastating threats due to invasive species

tree dead
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A team of researchers from Purdue University and the U.S. Department of Agriculture has found that trees in the United States are facing devastating threats due to invasive species. In their paper published in Proceedings of the National Academy of Sciences, the group describes analyzing thousands of forest plots across the U.S. and the mortality rates due to 15 major tree pest infestations, and what they found.

The United States has long been associated with large expanses of forest—but large-scale cutting has reduced forests over the past century. Now, confront a new threat—infestation by invasive pests unintentionally introduced into the country. Some infestations have already made headlines, such as the widespread loss of trees due to Dutch elm disease, the loss of most American chestnuts due to a fungal disease; additionally, ash borers have decimated ash tree populations in the Chicago area. In addition to providing wood-based products and beautiful parklands, forests are part of the carbon cycle—each tree sequesters a lot of carbon—when they die, they release that carbon into the atmosphere, contributing to global warming. Prior research has shown that there are now approximately 450 invasive tree pests in the U.S. that damage or kill trees. Most are believed to have been carried into the country through international trade and travel. In this new effort, the researchers set a goal of learning the scale of the threat U.S. forests face.

To gain some perspective on the threats to U.S. forestlands, the researchers carried out an analysis of 92,978 forest plots from across the country. They noted tree types in each plot and the rates of infestation by 15 major tree-killing pests.

The researchers found that approximately 40 percent of all forested land in the U.S. is under threat from invasive species. They also found that such pests are already killing so many trees that 6 million tons of carbon is released into the atmosphere each year. They note that not much can be done for already infected, but quarantine programs could be implemented to prevent the spread of pests.


Explore further

Traded forest tree seeds pose a great risk of introducing harmful pests

More information: Songlin Fei et al. Biomass losses resulting from insect and disease invasions in US forests, Proceedings of the National Academy of Sciences (2019). DOI: 10.1073/pnas.1820601116

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Citation: Trees in the U.S. facing devastating threats due to invasive species (2019, August 13) retrieved 23 August 2019 from https://phys.org/news/2019-08-trees-devastating-threats-due-invasive.html
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Aug 13, 2019
And after that comes the fires.

Aug 13, 2019
each tree sequesters a lot of carbon—when they die, they release that carbon into the atmosphere, contributing to global warming

Another steaming load of AGW Cult bullshit.
Gobble up, Chicken Littles.

Aug 13, 2019
each tree sequesters a lot of carbon—when they die, they release that carbon into the atmosphere, contributing to global warming

Another steaming load of AGW Cult bullshit.
Gobble up, Chicken Littles.


Not familiar with science, are you (rhetorical)?

Aug 13, 2019
^^^^^
LMAO.
I see a Chicken Shite gobbled it up.

Aug 13, 2019
^^^^^
LMAO.
I see a Chicken Shite gobbled it up.


Due to it being obvious and well known science. To those that aren't as thick as pigsh!t, such as yourself. Dummy.

Aug 13, 2019
@antigoracle.
Another steaming load of AGW Cult bullshit.
Gobble up, Chicken Littles.
It's amazing what "weaponised stupids" and/or bots can do on the net these days, hey @antigoracle? Anyhow, whatever you are, your daily betrayal of all that is ethical may earn you your 'thirty pieces of silver' for the moment, but your family/descendants will pay for it manyfold in the future. You have demonstrated that you and your GOP/Russian troll-factory-employed mates are such twisted/mercenary bots and/or weaponised-stupids that there's no hope of reason or humanity being realised in you or your programmers/handlers any time soon, @antigoracle. Pity.

Aug 13, 2019
^^^^^
LMAO.
I see a Chicken Shite gobbled it up.


Due to it being obvious and well known science. To those that aren't as thick as pigsh!t, such as yourself. Dummy.

Chicken Shite swallows their Cult's bullshit and believes it's brains.

Large amounts of dead trees, it turns out, hold on to their carbon for a long time and prevent it from quickly being released into the soil or the atmosphere

https://uanews.ar...expected

Aug 13, 2019
^^^^^Didn't read it properly, did you, dumbo?

Finally, the trees studied in this project grow at higher elevations, where cooler temperatures slow the decomposition process and thereby carbon-releasing respiration.


The fact that dead trees release carbon is a well known fact to anybody who has taken high school science. One can only assume you didn't. Or haven't reached high school yet. Thicko.

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