NUTRIENT CONCENTRATIONS IN Pinus ponderosa AND Pseudotsuga menziesii XYLEM SAP FROM ACID AND ALKALINE SOILS

Soil Science ◽  
1989 ◽  
Vol 148 (2) ◽  
pp. 124-131 ◽  
Author(s):  
N. STARK ◽  
D. ESSIG ◽  
S. BAKER
2003 ◽  
Vol 33 (5) ◽  
pp. 870-884 ◽  
Author(s):  
Rick G Kelsey ◽  
Gladwin Joseph

Sixteen days after a September wildfire, ethanol and water were measured in phloem and sapwood at breast height and the base of Pinus ponderosa Dougl. ex P. & C. Laws. with zero (control), moderate, heavy, and severe crown scorch. The quantity of ethanol increased with each level of injury, resulting in trees with severe scorch containing 15 and 53 times more phloem and sapwood ethanol, respectively, than controls. Ethanol concentrations in the sapwood and adjacent phloem were related, probably as a result of diffusion. Upward movement in xylem sap was most likely responsible for the relationship between sapwood ethanol concentrations at breast height and the stem base. As trees recovered from their heat injuries, the ethanol concentrations declined. In contrast, ethanol accumulated in dead trees that lost their entire crowns in the fire. Various bark and xylophagous beetles landed in greater numbers on fire-damaged trees than on controls the following spring and summer, suggesting that ethanol was being released to the atmosphere and influencing beetle behavior. Beetle landing was more strongly related to sapwood ethanol concentrations the previous September than in May. Sapwood ethanol measured 16 days after the fire was the best predictor of second-year mortality for trees with heavy and severe crown scorch.


2014 ◽  
Vol 324 ◽  
pp. 138-146 ◽  
Author(s):  
Gerald E. Rehfeldt ◽  
Laura P. Leites ◽  
J. Bradley St Clair ◽  
Barry C. Jaquish ◽  
Cuauhtémoc Sáenz-Romero ◽  
...  

1999 ◽  
Vol 77 (8) ◽  
pp. 1053-1076 ◽  
Author(s):  
H B Massicotte ◽  
R Molina ◽  
L E Tackaberry ◽  
J E Smith ◽  
M P Amaranthus

Seedlings of Abies grandis (Dougl.) Lindl. (grand fir), Lithocarpus densiflora (Hook. & Arn.) Rehd. (tanoak), Pinus ponderosa Dougl. ex Laws. (ponderosa pine), Pseudotsuga menziesii (Mirb.) Franco (Douglas-fir), and Arbutus menziesii Pursh (madrone) were planted in mixture and monoculture in soil collected from three adjacent forest sites in southwestern Oregon (a clearcut area, a 25-year-old Douglas-fir plantation, and a mature 90- to 160-year-old Douglas-fir - pine forest) to determine the effect of host tree diversity on retrieval of ectomycorrhizal morphotypes. In this greenhouse bioassay, 18 morphotypes of mycorrhizae were recognized overall from all soils with a total of 55 host-fungus combinations: 14 types with ponderosa pine, 14 with Douglas-fir, 10 with tanoak, 10 with grand fir, and 7 for madrone. Four genus-specific morphotypes were retrieved (three on ponderosa pine and one on Douglas-fir), even in mixture situations, demonstrating selectivity of some fungal propagules by their respective host. Five types were detected on all hosts, but not necessarily in soils from all sites. The remaining nine types were associated with two, three, or four hosts, which indicates a wide potential for interspecific hyphal linkages between trees. More morphotypes were retrieved from the monoculture treatments compared with the mixture treatments, although the differences were not significant. Several examples of acropetal replacement of one fungus by another (interpreted as succession) were recorded on all hosts during the course of the experiment. These results illustrate the importance of different host species in maintaining ectomycorrhizal fungus diversity, especially fungi with restricted host range, and the strong potential for fungal linkages between trees in forest ecosystems.Key words: fungal succession, fungal communities, compatibility, Arbutus menziesii, Pseudotsuga menziesii, Pinus ponderosa, Abies grandis, Lithocarpus densiflora.


2020 ◽  
Vol 29 (11) ◽  
pp. 1042
Author(s):  
Tyler R. Hudson ◽  
Ryan B. Bray ◽  
David L. Blunck ◽  
Wesley Page ◽  
Bret Butler

This work reports characteristics of embers generated by torching trees and seeks to identify the important physical and biological factors involved. The size of embers, number flux and propensity to ignite spot fires (i.e. number flux of ‘hot’ embers) are reported for several tree species under different combinations of number (one, three or five) and moisture content (11–193%). Douglas-fir (Pseudotsuga menziesii), grand fir (Abies grandis), western juniper (Juniperus occidentalis) and ponderosa pine (Pinus ponderosa) trees were evaluated. Embers were collected on an array of fire-resistant fabric panels and trays filled with water. Douglas-fir trees generated the highest average ember flux per kilogram of mass loss during torching, whereas grand fir trees generated the highest ‘hot’ ember flux per kilogram of mass loss. Western juniper produced the largest fraction of ‘hot’ embers, with ~30% of the embers generated being hot enough to leave char marks. In contrast, only 6% of the embers generated by ponderosa pine were hot enough to leave char marks. Results from this study can be used to help understand the propensity of different species of tree to produce embers and the portion of embers that may be hot enough to start a spot fire.


1999 ◽  
Vol 14 (1) ◽  
pp. 35-40 ◽  
Author(s):  
E. J. Zlatnik ◽  
T. H. DeLuca ◽  
K. S. Milner ◽  
D. F. Potts

Abstract The USDA Forest Service built terraces on the Bitterroot National Forest in the 1960s and 1970s as a means of mechanical site preparation prior to machine-planting ponderosa pine (Pinus ponderosa) in clearcuts. We examined the influence of terracing on planted ponderosa pine and soil characteristics more than 20 yr after site treatment and planting. Replicated plots at three separate paired (terraced/unterraced) sites were measured for tree diameter at breast height (dbh), total tree volume, planted tree volume and height, and understory biomass. Soil samples were analyzed for total C, Bray-1 extractable P, exchangeable K, soil pH, soil water-holding capacity, and particle size distribution. Terraced sites had significantly higher tree volumes, heights, and dbh, and higher silt contents than unterraced sites. Two of the three terraced sites also had greater understory biomass than the unterraced sites. Soil C and nutrient concentrations on terraced and unterraced pairs were generally similar. West. J. Appl. For. 14(1):35-40.


2014 ◽  
Vol 324 ◽  
pp. 147-157 ◽  
Author(s):  
Gerald E. Rehfeldt ◽  
Barry C. Jaquish ◽  
Cuauhtémoc Sáenz-Romero ◽  
Dennis G. Joyce ◽  
Laura P. Leites ◽  
...  

2014 ◽  
Vol 324 ◽  
pp. 126-137 ◽  
Author(s):  
Gerald E. Rehfeldt ◽  
Barry C. Jaquish ◽  
Javier López-Upton ◽  
Cuauhtémoc Sáenz-Romero ◽  
J. Bradley St Clair ◽  
...  

1999 ◽  
Vol 14 (4) ◽  
pp. 183-185
Author(s):  
Gladwin Joseph ◽  
Rick G. Kelsey

Abstract To test whether methanol or ethanol stimulated growth of coast Douglas-fir (Pseudotsuga menziesii vat. menziesii) or ponderosa pine (Pinus ponderosa) seedlings, we sprayed concentrations of 1 to 10% (v/v) on the foliage twice a week for 13 wk during the growing season. Foliar applications of methanol and ethanol neither significantly stimulated nor inhibited growth, and signs of damage at these concentrations were lacking. West. J. Appl. For. 14(4):183-185.


Sign in / Sign up

Export Citation Format

Share Document