scholarly journals Frequency, Severity, and Detectability of Internal Trunk Decay of Street Tree Quercus spp. in Tampa, Florida, U.S.

2016 ◽  
Vol 42 (4) ◽  
Author(s):  
Andrew Koeser ◽  
Drew McLean ◽  
Gitta Hasing ◽  
R. Bruce Allison

Wood decay is a factor considered in all commonly accepted tree risk assessment methods; however, few studies have attempted to assess its presence in the urban forest or its predictability given visual cues and site factors. A random sampling of trees situated on hurricane evacuation routes was inventoried and assessed for risk in the city of Tampa, Florida, U.S. In addition to a basic visual assessment, a sampling of larger diameter (>30.5 cm) live oak (Quercus virginiana) and all large diameter laurel oak (Quercus laurifolia) trees were tested with a resistance-recording drill to determine the amount of decay present (looking specifically at the sound-wood-to-stem-diameter ratio). Overall, 56.9% of the trees tested had some level of decay, though the incidence of decay was higher in laurel oak (67.4%) than in the live oak (29.4%). Additionally, tree species (P < 0.01), diameter (P < 0.01), and the presence or absence of visual decay indicators (P = 0.03) were all significant predictors of decay presence.

2002 ◽  
Vol 20 (2) ◽  
pp. 127-132
Author(s):  
Edward F. Gilman ◽  
Ann Stodola ◽  
Michael D. Marshall

Abstract Cutting propagated Quercus virginiana ‘QVTIA’ Highrise™ PP #11219 and seedling live oak required the same amount of time to prune to a dominant leader in the nursery. Highrise™ live oaks were more uniform in caliper, height and root ball characteristics than the seedling crop. Finished seedling trees had larger caliper than cutting propagated Highrise™ but height was similar. Root pruning horizontal roots alone or in combination with placing root pruning fabric under the liner at planting reduced dry weight of roots in the root ball by reducing large-diameter root weight and increasing small-diameter root weight. Trees produced by both methods of root pruning survived the digging process better than non root-pruned trees in the summer digging season. Seedlings had more root weight in the root ball and a higher root: shoot ratio than Highrise™ live oak. But Highrise™ had a 45% greater small diameter root: shoot ratio than seedling live oak, and more Highrise™ survived the digging process than seedlings. Highrise™ may not need root pruning during production if dug in the dormant season.


2016 ◽  
Vol 42 (2) ◽  
Author(s):  
Chris Haugen ◽  
Kevin Tucker ◽  
Alex Smalling ◽  
Emily Bick ◽  
Steve Hoover ◽  
...  

The plant growth regulator paclobutrazol’s effect on live oak trees (Quercus virginiana) was evaluated to determine optimum timing of application and pruning time in Louisiana. Variables considered included length of branch regrowth, branch distance to conductor, pruning time and biomass chipping time. Data were evaluated to determine the ideal application timing of paclobutrazol relative to time of pruning. Live oak trees treated with paclobutrazol had significantly reduced branch regrowth, pruning time and chipping time, as compared to control trees regardless of application timing. Paclobutrazol application on live oak trees was idealized within 90 days pre- to 90 days post-prune. Economically, significant gains were found by utilizing this tool ranging from 180 days pre- to 180 days post-prune, allowing for application timing flexibility to reduce the growth of trees near power lines. Paclobutrazol treated live oak trees demonstrated significantly less re-growth response.


2021 ◽  
Vol 71 (1) ◽  
pp. 39-41
Author(s):  
Darrel D. Nicholas

Abstract A need exists to develop improved test methods for evaluating potential wood preservatives in aboveground outdoor exposure. Our studies have shown that the three-component lap joint specified in AWPA Standard E27-15 represents an improved design for aboveground testing. One option for evaluating the extent of decay with this method relies on visual assessment. However, based on my observations in field tests, this assessment method does not provide an accurate measurement of the extent of wood biodeterioration in the early stages of decay. A second method of evaluation provided in this standard (in figure 4 of the standard) uses bending stiffness and dynamic modulus of elasticity (MOE) as alternate methods for determining the extent of decay, and this option was chosen to follow the progress of biodeterioration in this study. It was found that both of these methods provided an accurate assessment of decay in the early stages of biodeterioration that was superior to visual assessment. In an attempt to accelerate the rate of wood decay, some of the test units were treated with nitrogen-rich casein, and this resulted in a greater than twofold increase in the decay rate compared with the untreated controls. Another group of samples were treated with thiamin, but this resulted in only a slight increase in decay rate, whereas a combined treatment with both casein and vitamins resulted in a further increase in the decay rate beyond that of casein treated samples. Based on the results from this study, it is concluded that pretreatment of wood samples with thiamin has the potential for accelerating wood decay in aboveground test samples. Furthermore, the use of bending stiffness and dynamic MOE to measure the extent of wood decay was found to be superior to mass loss. Additional studies are needed to determine whether this concept could be useful in accelerating development of new wood preservatives.


2002 ◽  
Vol 32 (7) ◽  
pp. 1232-1243 ◽  
Author(s):  
Nathan J Poage ◽  
John C Tappeiner, II

Diameter growth and age data collected from stumps of 505 recently cut old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees at 28 sample locations in western Oregon (U.S.A.) indicated that rapid early and sustained growth of old Douglas-fir trees were extremely important in terms of attaining large diameters at ages 100–300 years. The diameters of the trees at ages 100–300 years (D100–D300) were strongly, positively, and linearly related to their diameters and basal area growth rates at age 50 years. Average periodic basal area increments (PAIBA) of all trees increased for the first 30–40 years and then plateaued, remaining relatively high and constant from age 50 to 300 years. Average PAIBA of the largest trees at ages 100–300 years were significantly greater by age 20 years than were those of smaller trees at ages 100–300 years. The site factors province, site class, slope, aspect, elevation, and establishment year accounted for little of the variation observed in basal area growth at age 50 years and D100–D300. The mean age range for old-growth Douglas-fir at the sample locations was wide (174 years). The hypothesis that large-diameter old-growth Douglas-fir developed at low stand densities was supported by these observations.


Weed Science ◽  
1970 ◽  
Vol 18 (4) ◽  
pp. 447-451 ◽  
Author(s):  
R. W. Bovey ◽  
M. L. Ketchersid ◽  
M. G. Merkle

Under Texas conditions, the potassium salt of 4-amino-3,5,6-trichloropicolinic acid (picloram) usually was more effective than the isooctyl ester formulation for control of live oak (Quercus virginianaMill.), yaupon(Ilex vomitoriaAit.), winged elm(Ulmus alataMichx.), huisache (Acacia farnesiana(L.) Willd.), and honey mesquite(Prosopis juliflora(Swartz) DC. var.glandulosa(Torr.) Cockerell). Possible reasons for the difference in effectiveness of picloram formulations were studied in the laboratory. Extensive degradation of the ester of picloram (96%) occurred in open Petri dishes after 72 hr exposure to ultraviolet (uv) light, compared to a loss of 26% for the salt of picloram. Forty-five percent of the isooctyl ester of picloram was lost at high temperatures (60 C), whereas only 2% of the potassium salt of picloram was lost after 1 week at 60 C from open Petri dishes in a dark oven. Application of the ester to soils reduced thermal and ultraviolet light degradation losses compared to losses from open Petri dishes. Loss of the ester was greater when applied in diesel oil to Petri dishes than in either water or paraffin oil. The salt of picloram leached most after 12.5 cm simulated rainfall in soil columns to the 17.5 to 30-cm level (907 μg), followed by the acid (360 μg), and last the isooctyl ester (0 μg). However, considerable acid (161 μg) was recovered at the 32.5 to 45-cm depth from the isooctyl ester treatment exposed to wet soils for 3 days, indicating hydrolysis of the ester to acid.


Weed Science ◽  
1980 ◽  
Vol 28 (3) ◽  
pp. 358-362 ◽  
Author(s):  
R. E. Meyer ◽  
R. W. Bovey

Hexazinone [3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4(1H,3H)-dione] was applied to honeylocust (Gleditsia triacanthosL.), honey mesquite [Prosopis juliflora(Swartz) DC. var.glandulosa(Torr.) Cockerell], huisache [Acacia farnesiana(L.) Willd.], live oak (Quercus virginianaMill.), Macartney rose (Rosa bracteataWendl.), post oak (Quercus stellataWangenh.), saw greenbrier (Smilax bona-noxL.), whitebrush (Aloysia lycioidesCham.), and yaupon (Ilex vomitoriaAit.). Bromacil (5-bromo-3-sec-butyl-6-methyluracil) and tebuthiuron {N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N′-dimethylurea} were used for comparison in some experiments. Hexazinone was required at the following rates to kill at least 75% of the following species: 1.1 kg/ha for live oak, 2.2 kg/ha for post oak, 4.5 kg/ha for huisache (at Bryan, Texas) and whitebrush, and 9 kg/ha for honeylocust. Hexazinone was ineffective at 9 kg/ha for control of honey mesquite, huisache (at Washington, Texas), Macartney rose, saw greenbrier, and yaupon. Tebuthiuron at 1.1 kg/ha killed 80% of the live oak, and as a subsurface spray at 4.5 kg/ha, killed huisache (at Washington, Texas). Bromacil was effective on huisache at 9 kg/ha.


2014 ◽  
Vol 133 (2) ◽  
pp. AB18 ◽  
Author(s):  
Mark C. Glaum ◽  
Eileen Rifkin ◽  
Jia-Wang Wang ◽  
Richard F. Lockey ◽  
Dennis K. Ledford

2004 ◽  
Vol 34 (1) ◽  
pp. 1-19 ◽  
Author(s):  
HE James Hammond ◽  
David W Langor ◽  
John R Spence

Saproxylic beetles associated with Populus coarse woody material were sampled from two age classes of fire-origin aspen stands in north-central Alberta, Canada. A combination of rearings from wood bolts and window traps attached to snags yielded 9571 beetles representing 257 taxa over the 3-year period (1993–1995). We investigated faunal variation across regions, stand ages (mature, 60–90 years; old, >100 years), decay classes, wood types, and years in terms of species richness, abundance, and trophic differences. Although trophic structure was similar, faunal composition differed between the two study regions. Species richness and abundance were similar across stand ages; however, many species were collected exclusively or in great majority from old stands and from snags of large diameter, which suggested that truncation of stand age structure through widespread industrial harvest could have serious consequences for saproxylic assemblages. Beetle species richness increased with the level of wood decay, whereas the total catch of beetles tended to be higher in early stages of decay. Wood borer abundance tended to be higher in snags; however, total species richness was higher in logs. Our analyses suggest that (i) many beetle species in the Canadian boreal forest depend directly upon standing and fallen large-diameter woody material from Populus trees, (ii) variation in stage of decay is critical to beetle diversity, and (iii) provision for retention of representative old stands is critical to conservation of saproxylic communities.


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