1923] PALMER, THE RED RIVER FOREST AT FULTON, ARKANSAS 15 



degrees it is a most favorable situation for the growth of many plants- 

 Near the top of this bluff and along the gravelly ridge above is found one 

 of the rarest of American Oaks, Quercus arkansana Sarg. This is near the 

 type locality where it was first discovered by Mr. B. F. Bush in 1909. 

 It is a small tree, seldom exceeding 10 meters in height with a trunk dia- 

 meter of 50 centimeters. It has rough dark furrowed bark resembling 

 that of the Black Oak. The foliage is somewhat similar to that of Quercus 

 marilandica but the leaves are much smaller, thinner and of a distinct 

 pattern. Its small fruit suggests affinities with Quercus nigra, but it 

 certainly is not a hybrid between them, and is indeed a very distinct 

 species. Within a radius of six or seven kilometers of the village of McNab 

 I have examined carefully scores of specimens of this curious Oak, and 

 doubtless many hundreds could be found, but it appears to be strictly 

 limited to the sand hills and small streams traversing them in the Fulton 

 region. Since becoming acquainted with it several years ago I have 

 made diligent seatch for it in other localities in Arkansas and surrounding 

 states where conditions appeared favorable, but so far it has proven 

 entirely fruitless. An interesting sequel is, however, that it has apparently 

 been found near Troy, Pike County, Alabama, where it was collected as 

 long ago as 1880 by Dr. Chas. Mohr, and in 1912 and 1913 by Dr. Roland 

 M. Harper. Dr. Harper's specimens in the Arnold Arboretum Herbarium 

 represent both the young leaves and flowers and the mature leaves with a 

 single fruiting cup. On Dr. Mohr's specimen, taken on July 4th, the 

 leaves are mature and fruit about half grown. In these specimens the 

 leaves are rather thinner and more nearly glabrous than in most of those 

 from the Fulton region, but some of the specimens from McNab closely 

 match them in these respects. In leaf type, scales of the fruit cup, winter 

 buds and other characters there is close resemblance. Indeed there is 

 fully as great a range of variability in all these respects between different 

 specimens taken near the type locality as between the type specimens and 

 those from the Alabama trees. Since the two localities are so far removed 

 from each other and, so far as present knowledge goes, Quercus arkansana 

 is comparatively rare and quite local at both places, the circumstance is 

 very interesting and its significance will be referred to later in this article. 

 Other Oaks growing along the upper portion of the bluff at McNab and 

 on the ridge above it are Quercus marilandica Muench., Q. alba L., Q. 

 Muhlenbergii Engelm., Q. Durandii Buckl. and Q. stellata Wang, and 

 a hybrid between the last two species, represented by a single tree, 

 also occurs. It is a tree 8 or 9 meters in height, with pale, slightly 

 flaky bark, more nearly resembling that of Q. Durandii. The variable 

 leaves and the fruit are quite intermediate between the two supposed 

 parents, both of which are growing in close proximity to the hybrid. 

 Lower down on the bluff are some fine specimens of Quercus Shumardii 

 Buckl., and Q. phellos L., Q. nigra L. and Q. lyrata Walt, are all growing in 

 low ground just below its base. On the dryer portions of the bluff are 



