35
March/April 2021
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THE DAVEY BULLETIN
You might not think of asphalt as something a Davey arborist
would use to care for trees, but asphalt was a key element
in tree care at Davey in the early and mid-20th century.
"Daveyite," as it was known in the early 1900s, was a
specially formulated pruning wound sealant. After Davey
arborists made pruning cuts they would apply Daveyite over
the wound as a means to seal it from weather, insects,
fungus and other elements. Using a brush, they would paint
the substance on the wound.
The Daveyite, as it was known until it was trademarked
as "DaveyKote" in 1948, had a base ingredient of asphalt.
But it was a special type of asphalt available only in three
locations around the world: Egypt, Trinidad and the
Wasatch Mountains in Utah. By 1938, the price of
Egyptian asphalt had risen to $600 per ton – making
it cost-prohibitive – whereas the material from Utah
cost just $65 per ton.
Davey arborists had to use one of these three special
asphalt bases. Other types of asphalt available at the
time contained oils and substances that could prove
harmful to the tree. And the "Daveyite" or "DaveyKote"
had to withstand severe summer heat without melting.
The use of Daveyite in the field was so common that
in 1938
alone Davey used more than 1,600 gallons of
the tar-like stuff.
ASPHALT-LIKE 'DAVEYKOTE' WAS EARLY ARBORISTS' TOOL
R.J. Laverne, manager of education and training, explained
that pruning wound sealers were intended to act like a
bandage to keep fungal spores off the pruning wound.
"This doesn't work because fungal spores are almost always
present and land on the pruning wound before the sealant
can be applied," he said. "Also, because sealants trap
moisture in and prevent sunlight from reaching the pruning
wound, they actually create a more favorable environment
for fungal spores to germinate."
Laverne said that on occasion sealants, particularly latex paint,
can be helpful in areas where Dutch elm disease or oak wilt
are prevalent as a means to keep trees infected with either
pathogen from emitting chemicals that can carry the diseases
into the air – thus limiting
the spread of the diseases.
Above: A "pot" of DaveyKote
pruning wound sealant sits on
the bed of a truck to be shipped
from the Davey Warehouse in
Kent along with Davey Tree
Food and other materials in
the late 1940s.
Left: A "pot" of DaveyKote
pruning wound sealant. Davey
slowly phased out its use in
the mid-to-late 1900s.
FROM THE ARCHIVES
