Beginning in the early 1980s, there were reports of white oak ( Quercus alba L.) leaves losing interveinal tissues throughout the Midwest [ Green, 1985 ; Haugen et al., 2000 ; Leatherberry et al., 2004 ; Wisconsin Department of Agriculture
Jayesh B. Samtani, John B. Masiunas and James E. Appleby
Jayesh B. Samtani, John B. Masiunas and James E. Appleby
.O. Phelps, J.E. Hinckley, T.M. 1979 Net photosynthesis and early growth trends of dominant white oak ( Quercus alba L.) Plant Physiol. 64 930 935 Elias, T.S. 1987 The complete trees of North America Crown
Orville M. Lindstrom
The cold hardiness of seven deciduous hardwoods, red maple (Acer rubrum L.), white oak, (Quercus alba L.), green ash (Fraxinus pennsylvanica Marsh.), sweetgum (Liguidambar stryaciflua L.), sugar maple (Acer saccharum Marsh.), river birch (Betula nigra L.) and black cherry (Prunus serotina Ehrh.) were evaluated weekly during the fall, winter and spring for three consecutive years. All trees evaluated were established (20-40 years old) and locatd on the Georgia Station Griffin, GA. Each species developed a maximum cold hardiness of at least -30 C by mid-January or early February each season. Response to temperature fluctuations varied with species. Red maple, for example, lost less cold hardiness due to warm mid-winter temperatures than the other species tested, while white oak tended to respond more quickly to the temperature fluctuations. Data will be presented comparing the response of cold hardiness to mid-winter temperature fluctuations for each species for the three year period.
Robert M. Augé, Xiangrong Duan, Jennifer L. Croker, Craig D. Green and Will T. Witte
We compared the potential for foliar dehydration tolerance and maximum capacity for osmotic adjustment in twelve temperate, deciduous tree species, under standardized soil and atmospheric conditions. Dehydration tolerance was operationally defined as lethal leaf water potential (Ψ): the Ψ of the last remaining leaves surviving a continuous, lethal soil drying episode. Nyssa sylvatica and Liriodendron tulipifera were most sensitive to dehydration, having lethal leaf Ψ of –2.04 and –2.38 MPa, respectively. Chionanthus virginiana, Quercus prinus, Acer saccharum, and Quercus acutissima withstood the most dehydration, with leaves not dying until leaf psi dropped to –5.63 MPa or below. Lethal leaf Ψ (in MPa) of other, intermediate species were: Quercus rubra (–3.34), Oxydendrum arboreum (–3.98), Halesia carolina (–4.11), Acer rubrum (–4.43), Quercus alba (–4.60), and Cornus florida (–4.88). Decreasing lethal leaf Ψ was significantly correlated with increasing capacity for osmotic adjustment. Chionanthus virginiana and Q. acutissima showed the most osmotic adjustment during the lethal soil drying episode, with osmotic potential at full turgor declining by 1.73 and 1.44 MPa, respectively. Other species having declines in osmotic potential at full turgor exceeding 0.50 MPa were Q. prinus (0.89), A. saccharum (0.71), Q. alba (0.68), H. carolina (0.67), Q. rubra (0.60), and C. florida (0.52). Lethal leaf Ψ was loosely correlated with lethal soil water contents and not correlated with lethal leaf relative water content.
Jason Grabosky and Nina Bassuk
In the development of a street tree planting medium for use as a sidewalk base, we have been testing a series of limestone gravel and soil media with varied amounts of clay loam suspended within the matrix voids. Tilia cordata and Quercus alba seedling roots quickly penetrated and grew in these systems when compacted to densities in excess of 2000 kg·m–3, while they were severely impeded in clay loam soil compacted to 1300 kg·m–3. Limestone mixes of the same design had variable, but consistently acceptable, California Bearing Ratios (>40) when compacted to similar densities; demonstrating their strength as a pavement base. Tilia root growth, based on the volume collected from total root excavations after two growing seasons, increased a minimum of 300% in the limestone mixes over the compacted clay loam control when the treatments were compacted to ≈80% Standard Proctor Optimum Density. Root penetration of Quercus increased >400% in the limestone mixes over compacted loam in a 6-month trial compacted to 95% Standard Proctor Optimum Density.
Tomás Martínez-Trinidad, W. Todd Watson and Russell K. Book
on trees treated with the full rate of PBZ and root pruned at 45 cm ( Figs. 1 and 2 ). A similar result was found on trunk growth or canopy growth in species such as white oak ( Quercus alba ), red oak ( Quercus rubra ), cherrybark oak ( Quercus
Robert D. Wright, Brian E. Jackson, Jake F. Browder and Joyce G. Latimer
. Supportive of our work, Still et al. (1972) reported chrysanthemums grown in white oak ( Quercus alba ) sawdust and fertilized at 400 mg·L −1 N had growth comparable with a peat-based substrate, and Gruda and Schnitzler (1999) showed that extra N during
) found that applications of N at intervals of 10 to 12 d maintained continuous elongation in first-year red oak and white oak ( Quercus alba ) seedlings. Sparks and Baker (1975) found that moderate amounts of ammonium nitrate stimulated growth of second
Emily G. Tenczar and Vera A. Krischik
deterrents, even to specialist insects ( Rhodes and Cates, 1976 ). In quaking aspen ( Populus tremuloides Michx.), higher tannin levels decreased cottonwood leaf beetle larval growth rate by 30% ( Donaldson and Lindroth, 2004 ). In white oak ( Quercus alba
YanLing Zheng, GaoJuan Zhao and HuanCheng Ma
Connor, K.F. Sowa, S. 2003 Effects of desiccation on the physiology and biochemistry of Quercus alba acorns Tree Physiol 23 1147 1152 Ellis, R.H. Hong, T.D. 1994 Desiccation tolerance and potential longevity of developing seeds of rice ( Oryza sativa L