scholarly journals Effect of Uniconazole on Shoot Growth and Budset of Containerized Fraser Fir

HortScience ◽  
1998 ◽  
Vol 33 (1) ◽  
pp. 82-84 ◽  
Author(s):  
L. Eric Hinesley ◽  
Stuart L. Warren ◽  
Layne K. Snelling

In two experiments, uniconazole (0.25 to 16 mg·L-1 a.i.) was applied as a root drench to containerized Fraser fir [Abies fraseri (Pursh) Poir.] at various times of the year. Leader length, stem diameter, length of laterals, and number of subterminal buds were reduced the following growing season. Treatment during the 1994 growing season reduced lateral bud formation on the leader in 1995, whereas treatment with 8 or 16 mg·L-1 in Mar. 1995 (prior to budbreak) increased it. Uniconazole caused needle discoloration and abscission at concentrations ≥4 mg·L-1. Leader growth was reduced more than branch elongation, which tended to make plants more decurrent. The utility of uniconazole in production of tabletop Fraser fir Christmas trees was unclear; reduced shoot elongation was often accompanied by fewer lateral buds and needle discoloration and/or abscission. Chemical name used: E-1-(p-Chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazole-1-penten-3-ol) (uniconazole).

2013 ◽  
Vol 23 (3) ◽  
pp. 294-300 ◽  
Author(s):  
Linglong Wei ◽  
Jarrod J. Morrice ◽  
Rodney V. Tocco ◽  
Bernard H. Zandstra

Experiments were conducted to test a new herbicide for posttransplant application in Christmas trees. A premix containing 68.6% hexazinone and 6.5% sulfometuron-methyl was applied at 3.0, 4.5, 6.0, 7.5, and 9.0 oz/acre plus 0.25% v/v nonionic surfactant (NIS) to recently transplanted fraser fir (Abies fraseri) Christmas trees and trees transplanted for 1 year in Spring 2008. The treatments were repeated on the same plots in 2009 and 2010. At Gobles, MI, trees treated with 7.5 oz/acre of hexazinone plus sulfometuron had increased stem diameter, after one growing season, and trees treated with 9.0 oz/acre had reduced leader length the second year. After 3 years, fraser fir trees treated with hexazinone plus sulfometuron at 9.0 oz/acre had reduced tree height. Stem diameter, leader length, and number of leader buds were not statistically different from the untreated control. At Horton, MI, trees treated with 9.0 oz/acre of hexazinone plus sulfometuron had reduced leader length after 1, 2, and 3 years. After 3 years, trees treated with hexazinone plus sulfometuron at 6.0, 7.5, and 9.0 oz/acre were shorter than the untreated controls. There were no differences from the untreated trees in stem diameter of trees treated with hexazinone plus sulfometuron after 3 years.


2001 ◽  
Vol 11 (1) ◽  
pp. 151b
Author(s):  
L. Eric Hinesley ◽  
Layne K. Snelling ◽  
C. Ray Campbell ◽  
D.K. Roten ◽  
Jeff Hartzog

Abstract. Abies fraseri (Pursh) Poir. Christmas trees were fertilized for 5 years with four levels of N (0, 56, 113, or 170 kg·ha-1 per year) in spring, fall, or equally split between spring and fall. Nitrogen did not affect leader length, number of leaders, or bud frequency on the upper (distal) portion of the leader. Nitrogen increased bud frequency on the lower (proximal) 20 cm of the leader in only 1 of 3 years of measurement. All application schedules increased the number of apical buds on branches, whereas the number of lateral buds was increased only by spring applications. Nitrogen increased tree fresh weight and retail value as well as weight, length, and surface area of needles. Foliar N concentrations in the fall varied with fertilization schedule, and were higher in November than in October.


2008 ◽  
Vol 25 (1) ◽  
pp. 52-54 ◽  
Author(s):  
Pascal Nzokou ◽  
Bert M. Cregg ◽  
Jill O'Donnell

Abstract Excessive leader growth is a challenge for Christmas tree growers who are seeking about 30–35 cm (12–14 in.) shoot elongation for good balance between height and lateral growth. Current cultivation practices include manually pruning leaders to 30–35 cm. In this studywe investigated the use of a growth regulator Ethyl-naphthaleneacetate acid (NAA) and a girdling process using a five-bladed plier (Top-Stop Nipper, Monterey Lawn and Gardens Products, Inc., Fresno, CA) as alternative methods to slow leader growth in Fraser fir (Abies fraseri [Pursh]Poir.), and Korean fir (Abies koreana Wils). NAA applications at rates of 40–160 ml/L reduced the height growth in both Fraser fir and Korean fir. However, in Fraser fir, other morphological parameters such as the leader straightness and bud density were generally adversely affected.The highest rates of 250 and 500 ml/l caused unacceptable reduction in growth and in many cases leader death. NAA applications on Korean fir resulted in significant reduction of leader growth and significantly increased the bud density without negative impact on leader straightness. Partialgirdling of stems was not effective at reducing the leader height in both Fraser fir and Korean fir.


HortScience ◽  
1995 ◽  
Vol 30 (2) ◽  
pp. 260-264 ◽  
Author(s):  
L. Eric Hinesley ◽  
Layne K. Snelling

Various pruning treatments were evaluated to determine the best procedure to correct terminal bud loss in Fraser fir [Abies fraseri (Pursh) Poir.]. Removing the top node (expanding terminal and subterminal buds) soon after budbreak combined with light pruning of the major branches in the next two lower whorls best restored a normal leader. This procedure allowed one or more shoots just below the cut to become orthotropic leaders in the first growing season. All but one of these shoots were removed, and only a single leader was retained after growth matured in late August or September.


HortScience ◽  
2000 ◽  
Vol 35 (5) ◽  
pp. 860-862 ◽  
Author(s):  
L. Eric Hinesley ◽  
Layne K. Snelling ◽  
C. Ray Campbell ◽  
D.K. Roten ◽  
Jeff Hartzog

Abies fraseri (Pursh) Poir. Christmas trees were fertilized for 5 years with four levels of N (0, 56, 113, or 170 kg·ha–1 per year) in spring, fall, or equally split between spring and fall. Nitrogen did not affect leader length, number of leaders, or bud frequency on the upper (distal) portion of the leader. Nitrogen increased bud frequency on the lower (proximal) 20 cm of the leader in only 1 of 3 years of measurement. All application schedules increased the number of apical buds on branches, whereas the number of lateral buds was increased only by spring applications. Nitrogen increased tree fresh weight and retail value as well as weight, length, and surface area of needles. Foliar N concentrations in the fall varied with fertilization schedule, and were higher in November than in October.


HortScience ◽  
1997 ◽  
Vol 32 (2) ◽  
pp. 324-326 ◽  
Author(s):  
L. Eric Hinesley ◽  
Layne K. Snelling

Fraser fir [Abies fraseri (Pursh) Poir.] Christmas trees were basal pruned (branches were removed from the lower 15 to 25 cm of the stem, i.e., handle) at heights ranging from 0.6 to 0.9 m up to 1.5 to 1.8 m tall, and were harvested 2 to 4 years later. Basal pruning reduced cutting time ≈25%, and baling time ≈10%. Commercial height and stem diameter were unaffected, but the average harvest weight of pruned trees 2.1 to 2.4 m tall (2 to 4 years after basal pruning) was reduced ≈1.4 kg.


2018 ◽  
Vol 150 (5) ◽  
pp. 632-636 ◽  
Author(s):  
Jean-Frdéric Guay ◽  
Amy Bernier-Desmarais ◽  
Jean-François Doherty ◽  
Conrad Cloutier

AbstractThe pine needle scale, Chionaspis pinifoliae (Fitch) (Hemiptera: Diaspididae), has the status of an emerging pest in Christmas tree (Pinaceae) plantations in Québec, Canada. The scale is not known to cause any significant damage yet and is not generally monitored by growers. However, it can be an obstacle for exportation to Christmas tree markets where scale insects are strictly regulated. In this study, we describe its life cycle in Christmas tree plantations in southern Québec. We confirm the presence of both parthenogenetic and sexual forms of the scale on Fraser fir Abies fraseri (Pursh) Poiret (Pinaceae) grown as Christmas trees, and of parasitoid and Coccinellidae (Coleoptera) specialists that could contribute to its control.


1971 ◽  
Vol 49 (10) ◽  
pp. 1821-1832 ◽  
Author(s):  
Edward Sucoff

During the 1969 and 1970 growing season buds were collected almost weekly from matched trees in northeastern Minnesota. Cataphyll primordia for the year n + 1 shoot began forming at the time that internodes in the year n shoot started elongating (late April) and continued forming until early September. Primordia for axillary buds started forming about 2 months later and stopped forming at the same time as cataphylls. The size and deposition activity of the apical dome simultaneously increased during the early growing season and decreased during the late season. The maximum rates in July were over nine cataphylls per day.Rate of cataphyll deposition paralleled elongation of the needles on subtending shoots. Forty to fifty percent of the cataphylls had been formed when shoot growth was 95% complete. Although the bulk of the depositions occurred earlier in 1970, when growing degree days were used as the clock, the 2 years were similar.The results provide quantitative data to complement the histologic emphasis of previous studies.


1984 ◽  
Vol 14 (3) ◽  
pp. 447-451 ◽  
Author(s):  
C. H. A. Little

The entire crown of variously fertilized, unsheared Abiesbalsamea (L.) Mill. trees was sprayed once or twice weekly for 2, 4, or 8 weeks with an aqueous solution of 0 or 600 mg 6-benzylaminopurine (BAP) L−1 containing 1.5% dimethyl sulfoxide, 13.5% methanol, and 0.1% Tween 20, starting at different times during the period of shoot elongation. In the year of application, BAP inhibited the elongation of the current-year shoot, increased the number of lateral buds formed on this shoot, and induced lammas growth. Both BAP and the carrier solution caused some phytotoxicity in current-year needles. Responses to BAP treatment varied markedly with genotype, whorl position, and time of application, and decreased with mineral deficiency, and decreasing BAP dosage. After overwintering, many of the BAP-induced lateral buds elongated, resulting in an increased number of shoots, hence in a denser crown.


1981 ◽  
Vol 11 (4) ◽  
pp. 789-795 ◽  
Author(s):  
S. Thompson

When seedlings of a single seed source of Scots pine (Pinussylvestris L.) were raised for 26 weeks in a naturally lit, heated greenhouse, two types of shoot morphology were observed. Type 1 was that normally found in 1-year-old seedlings. Type 2 had a shoot morphology similar to that of seedlings raised outdoors for two growing seasons. When compared with type 1 plants, type 2 plants had an earlier start to shoot elongation, set their buds earlier, and stopped shoot elongation sooner. After one growing season, type 2 plants were shorter, had fewer stem units for shoot elongation in the second season, but carried a greater foliage biomass than 1-year-old type plants. After two seasons they remained shorter. Thus, plant rearing practices which result in the production of seedlings with this type of shoot morphology arc undesirable.The relationship between early "budsct," shoot morphology, and plant height suggests that the proportion of seedlings with a 2-year-old shoot morphology after one growing season in a heated greenhouse may be used as an early test for height growth potential in seed origins and possibly in progenies of north temperate pine species.


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