White oak
General poisoning notes:
White oak (Quercus
alba) is a native tree found in southern Quebec and Ontario. Ingesting the
leaves and acorns has caused some toxic problems in cattle. The concentration
of toxic phenolics is less than in red or black oak (Q. rubra or Q.
velutina). Symptoms are similar for all three species of oak. In severe
cases, renal failure usually results in death (Sandusky et al. 1977, Cockrill
and Beasley 1979).
Description:
Trees , deciduous,
to 25 m. Bark light gray, scaly. Twigs green or reddish, becoming gray, 2-3(-4)
mm diam., initially pubescent, soon glabrous. Buds dark reddish brown, ovoid,
ca. 3 mm, apex obtuse, glabrous. Leaves: petiole (4-)10-25(-30) mm. Leaf blade
obovate to narrowly elliptic or narrowly obovate, (79-)120-180(-230) ×
(40-)70-110(-165) mm, base narrowly cuneate to acute, margins moderately to
deeply lobed, lobes often narrow, rounded distally, sinuses extending 1/3-7/8
distance to midrib, secondary veins arched, divergent, (3-)5-7 on each side,
apex broadly rounded or ovate; surfaces abaxially light green, with numerous
whitish or reddish erect hairs, these quickly shed as leaf expands, adaxially
light gray-green, dull or glossy. Acorns 1-3, subsessile or on peduncle to
25(-50) mm; cup hemispheric, enclosing 1/4 nut, scales closely appressed,
finely grayish tomentose; nut light brown, ovoid-ellipsoid or oblong,
(12-)15-21(-25) × 9-18 mm, glabrous. Cotyledons distinct. 2 n = 24.
Nomenclature:
Scientific Name: Quercus alba L.
Vernacular name(s): white oak, eastern
white oak, chêne blanc.
Scientific family name: Fagaceae
Vernacular family name: beech
Geographic Information:
Ontario, Quebec.
Toxic parts:
Acorns, leaves.
Notes on Toxic plant chemicals:
See notes under chemicals in red oak
(Quercusrubra).
Toxic plant chemicals:
Gallic acid, pyrogallol, tannic acid.
Animals/Human Poisoning:
Note: When an animal is listed
without additional information, the literature (as of 1993) contained no
detailed explanation.
Cattle
General symptoms of poisoning:
Anorexia, ascites, death,
dehydration, depression, diarrhea, kidney failure.
Notes on poisoning:
Toxic symptoms include anorexia,
rumen atony, hemorrhagic diarrhea, subcutaneous edema, ascites, and
dehydration. Renal failure usually results in death. Postmortem examination
revealed perirenal edema and hemorrhage. The kidneys had a characteristic nephrosis
in a multifocal pattern, of the proximal convoluted tubules (Sandusky et al.
1977, Cockrill and Beasley 1979).
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