Variation in Cold‐Hardiness of Fraxinus Americana Stem Tissue According to Geographic Origin

Abstract

Cold—hardiness of stem sections of white ash (Fraxinus americana L.) from 10 geographic origins in eastern North America, growth in a provenance planting in south Michigan, was determined by controlled freezing. Northern plants were more cold—hardy than southern plants in early and midwinter, but differences disappeared by early spring. Substantial variation in cold—hardiness was found among trees within each origin. Multiple regression of killing temperatures on latitude, longitude, elevation, average annual minimum temperature, and annual frost—free period proved useful in predicting cold—hardiness, and may be useful in forecasting performance of trees in locations removed from their sites of origin.

Effects of excess nitrogen on frost hardiness and freezing injury of above‐ground tissue in young oaks (Quercus petraea and Q. robur)

“…In the present study, values of that magnitude were obtained in April, after a distinct increase in the minimum air temperature. These results represent an additional corroboration of the method and indicate its suitability for quantifying the state of frost hardiness in plant tissues (Alexander et al, 1984 ;Burr et al, 1990).…”

“…Thus, we conclude that the vitality of bark tissue from frost-exposed indigenous oak species is noticeably decreased if an I −#& of 15 % (as determined under the selected conditions) is exceeded. Accordingly, for twigs of Fraxinus americana subjected to the same test of frost hardiness, freezing temperatures resulting in an index of injury of 15 % were regarded as ' killing temperatures ' (Alexander et al, 1984). For twigs of Quercus rubra, temperatures yielding an index of injury of 10 % were regarded as critical (Flint, 1972).…”

“…To assess the frost hardiness of plants, Flint et al (1967) suggested calculating an index of injury from the relative electric conductivities of solutions in which the samples had been incubated. This method has been widely adopted to test the frost hardiness of various parts of trees such as stem sections (van den Driessche, 1976), twigs (Alexander et al, 1984) and needles (Burr et al, 1990). More recently, Murray et al (1989) developed a method based on the rate of electrolyte leakage, which has been used successfully to quantify the freezing injury to woody shoots in, for example, Calluna vulgaris (Caporn et al, 1994), Quercus petraea (Deans et al, 1995) and Picea abies (Sheppard et al, 1995).…”

Variation de la résistance au gel au printemps et en automne entre et dans les populations espagnoles sauvages de Castanea sativa

“…Other authors have also found significant differences among populations of different temperate species for injury traits in different seasons in Fraxinus americana L. (Alexander et al, 1984), Alnus rubra Bong. (Cannell et al, 1987), Q. petraea (Deans and Harvey, 1996;Jensen and Deans, 2004) and in P. trichocarpa (McCamant and Black, 2000) and for other cold adaptation traits, such as timing of phenological events in Q. robur L. (Jensen and Deans, 2004), and in J. regia L. (Díaz et al, 2006).…”

The effect of excess nitrogen and of insect defoliation on the frost hardiness of bark tissue of adult oaks

“…Defoliation as well can lower the frost hardiness in the following winter (Sakai and Larcher, 1987). Since insect defoliation is one of the primary causal factors of oak decline in northern Germany, and since the majority of oak stands investigated in northwestern Germany had shown high leaf nitrogen contents as compared to literature data (Thomas and Büttner, 1992; Thomas and Kiehne, 1995) Driessche, 1969;Green and Warrington, 1978), lateral shoots (Dueck et al, 1990(Dueck et al, /1991Sheppard et al, 1994), and pieces of twigs (Alexander et al, 1984) and needles (Aronsson, 1980;Kolb et al, 1985;Burr et al, 1990), but only rarely in bark tissue (Ashworth et al, 1983 (1985). The samples were cooled down to two freezing levels: -10 or -15 °C, respectively, and -25 °C.…”