Florida YewTop
Florida yew is an evergreen shrub or small tree, rarely to 25' and usually less
than 15' tall. It has numerous spreading, horizontal branches that give it a bushy
appearance. The leaves are needle-like and flat, about an inch long and grow in two
horizontal ranks on opposite sides of the twigs. The bark is purplish-brown, smooth on
young stems and separating into thin irregular scales on older branches. Florida yew is
dioecious and in October the female plants bear oval, half-inch long fruits that consist
of a single yellowish-brown seed partly enclosed in a fleshy red cup. Florida yew is
similar to the Florida torreya (Torreya taxifolia), another exceedingly rare tree in the
yew family. The two species have almost identical distributions, and can be told apart by
examining the needles. The torreya has sharp, stiff needles, whereas the yew has soft,
flexible needles. Also, the torreya foliage smells like tomato leaves, and the yew foliage
smells more like turpentine. Top
Location
Florida yew is one of the rarest trees in the world and is listed as an
Endangered Species by state and federal agencies. Florida yew occurs only in forested
bluffs and ravines scattered along a 15-mile reach on the east side of the Apalachicola
River between Chattahoochee and Bristol in Gadsden and Liberty Counties, Florida. It grows
in clumps or small clonal stands within mesic forests dominated by American beech,
southern magnolia, American holly, and white oak. Some populations of Florida yew are
protected at Torreya State Park and at The Nature Conservancy's Apalachicola Bluffs and
Ravines Preserve, and these are the best places to see the tree. Other populations are on
privately-owned land, and are vulnerable to destruction. (Note that US and Florida
Endangered Species laws DO NOT provide protection for endangered plants on private
property.) Top
Culture
Florida yew is slow-growing. It likes a slightly acidic soil.
Light: Grows well in partial to almost full shade.
Moisture: Moderately drought tolerant.
Hardiness: USDA Zone 8. Hardiness range not known. Florida yew grows naturally in USDA
zone 8B. Other species of yew are very cold-hardy.
Propagation: Can be propagated from seed or cuttings. Seeds may require warm and cold
stratification. Mature wood cuttings taken in winter can be rooted under mist. Top
Usage
Florida yew is rarely found in cultivation. If you can grow a yew, it certainly
would make an interesting specimen or background shrub. And, you would be helping to
prevent the extinction of this rare tree! Other species of Taxus (there are only eight
species, but there are many popular cultivars in the trade) are used for hedges and
topiary as well as specimen plants. Top
Features
The bark of Florida yew contains the promising cancer-fighting compound taxol
in amounts similar to Pacific yew (T. brevifolia). Pacific yew has been harvested for
taxol, and the threat that the endangered Florida yew might also be harvested has worried
conservationists. Fortunately, researchers recently have developed methods to synthesize
taxol in the laboratory and methods to produce taxol with bioengineered fungus. Scientists
at Florida State University in Tallahassee were the first to synthesize taxol in 1993, and
since then FSU has reaped more than $100 million in royalties from Bristol-Myers Squibb.
That same year scientists from Montana State University in Bozeman discovered that taxol
is produced by a fungus that grows in association with yew trees. Now researchers at MSU
and Cytoclonal Pharmaceutics are scientifically manipulating several fungi and bacteria
species to make commercial amounts of taxol. Taxol has been proven useful in treating
breast cancer, ovarian cancer, some kinds of leukemia, and certain kidney diseases. Top
WARNING
The seeds and foliage of all the yew species are extremely
poisonous, and people have died from eating the seeds or drinking a tea made from the
leaves. Top