New-Ground Syndrome: An Ectomycorrhizal Deficiency in Pine Nurseries

1988 ◽  
Vol 12 (4) ◽  
pp. 234-239
Author(s):  
David B. South ◽  
R. J. Mitchell ◽  
R. K. Dixon ◽  
Mark Vedder

Abstract In July 1986, stunted loblolly pine (Pinus taeda L.) seedlings were studied at a nursery in Union Springs, Alabama. Stunted seedlings were found only in seedbeds formed on new ground (soil having no history of producing a nursery crop of ectomycorrhizal tree seedlings). The stunted seedlings were either nonmycorrhizal or had extremely low levels of ectomycorrhizae, whereas nonstunted seedlings had a greater degree of ectomycorrhizal development. Stunted seedlings were deficient in phosphorus (0.07%), whereas nonstunted seedlings had sufficient phosphorus (0.15%). An application of phosphoric acid (H3PO4) to stunted seedlings increased shoot phosphorus and resulted in substantial growth improvement. The phosphorus application reduced the percentage of cull seedlings (root-collar diameter <3.2 mm) from 62% to 8%. This study also demonstrates that when a seedbed is formed on new ground, ectomycorrhizal deficiencies can occur even when ectomycorrhizal tree hosts are present in the immediate vicinity. The ectomycorrhizal deficiency in the seedlings observed in this study may have been related to restricted spore dispersal caused by insufficient rainfall that had occurred after spring fumigation. South J. App. For. 12(4):234-239.

1982 ◽  
Vol 6 (1) ◽  
pp. 30-33 ◽  
Author(s):  
John L. Ruehle

Abstract Container-grown loblolly pine seedlings (Pinus taeda L.) with Pisolithus tinctorius, Thelephora terrestris, or no ectomycorrhizae (control) were outplanted on a South Carolina reforestation site. Two years after planting, seedlings initially colonized with Pisolithus or Thelephora had greater survival, height, and root collar diameter than control seedlings. Growth data were integrated into seedling volume indices (D²H). Seedlings with ectomycorrhizae at planting had nearly a three-fold greater D²H than seedlings initially without ectomycorrhizae. These results provided additional field validation for the hypothesis regarding benefits of ectomycorrhizae on this type of planting stock.


1990 ◽  
Vol 14 (3) ◽  
pp. 109-114 ◽  
Author(s):  
Barry D. Shiver ◽  
Bruce E. Borders ◽  
Henry H. Page ◽  
Steven M. Raper

Abstract A seedling survival study for site-prepared loblolly pine (Pinus taeda L.) plantations, consisting of 43 locations, was established during two planting seasons in 1986-87 in the Georgia Piedmont. Seedlings with top lengths less than 15 cm and with root collar diameters less than 2.5 mm survived significantly worse than larger seedlings, but such small seedlings comprised less than 2% of seedlings bagged and planted in the study. Culling in the field to eliminate such a small percentage of seedlings in addition to culling already done at the nursery is probably not worth the expense from a survival standpoint. Terminal bud condition was not related to survival. Seedlings planted deeper than root collar diameter survived the same as seedlings planted at root collar depth, but shallow planted seedlings had significantly poorer survival. Very loosely planted seedlings were more likely to die than firmly planted seedlings, but slightly loose seedlings survived as well as tightly planted seedlings. Differences between operationally planted and experimentally planted plots indicated that an average 10% increase in survival was possible from close planting crew supervision. Over 90% of first-year mortality occurred on both operationally and experimentally planted plots by the end of July. South. J. Appl. For. 14(3):109-114.


2000 ◽  
Vol 24 (3) ◽  
pp. 135-139 ◽  
Author(s):  
William A. Carey

Abstract The effects of soil fumigation with chloropicrin alone or in combination with metham sodium and or with EPTC on the growth of loblolly pine (Pinus taeda L.) seedlings and on nutsedge (Cyperus spp.) control were investigated at three forest tree nurseries. Fumigation with chloropicrin plus metham sodium (CMS) significantly increased seedling numbers and growth compared to controls. Averaged among nurseries, mean root-collar-diameter increased from 0.14 to 0.17 in., and biomass from 0.14 to 0.20 lb/ft2. This produced seven more plantable seedlings and 6.5 more grade 1 seedlings/ft2 in CMS compared to not fumigated plots. Fumigation increased average potential sales $7,100/ac and increased present values, projected for the growth increases for additional grade 1 seedlings, by $25,900/ac. Fumigation increased biomass per unit area similarly at tested bed densities (10 to 29/ft2), but at low bed densities (≤20/ft2) the present values associated with grade 1 seedlings increased more than at higher densities. South. J. Appl. For. 24(3):135-139.


2007 ◽  
Vol 64 (1) ◽  
pp. 23-29
Author(s):  
José Geraldo de Araújo Carneiro ◽  
Deborah Guerra Barroso ◽  
Luis Maurício da Silva Soares

Seedlings compete for nutrients, water and light. The available area for each seedling affects their behavior related to requirements for these resources. This experiment evaluated the influence of five plant densities on the growth of bare root Pinus taeda, L. seedlings in a nursery after outplanting. The analyzed characteristics were: height (H), root collar diameter (D), H/D ratio, and dry matter weight. Higher densities stimulated H growth and the lowest densities increased D average and dry matter weight and lowered the H/D ratio. Seedlings were distributed by H, D and H/D classes. Higher densities had a larger number of seedlings in larger H classes. Larger numbers of seedlings with larger D and lower H/D ratios were found in lower densities. Ten months after outplanting the seedlings grown in lower densities had higher survival percentages and growth. Some saplings of standardized heights were uprooted with the objective of studying their root systems. The lowest densities stimulated higher numbers of first and second order roots as well as fresh and dry matter weights of thin roots with mycorrhizae presence. In both parts of the experiment, the density of 278 seedlings m-2 yielded equivalent averages as compared to the lowest densities.


1984 ◽  
Vol 8 (2) ◽  
pp. 109-112 ◽  
Author(s):  
B. Graeme Lockaby ◽  
Clyde G. Vidrine

Abstract Soil bulk densities, determined on plots representing a gradient of harvesting traffic, indicated that compaction was an average of 12 percent greater on former logging decks and primary skid roads as compared to nontrafficked areas. Penetrometer readings supported the bulk density results and, in addition, showed increased compaction on secondary roads and road borders as compared to relatively undisturbed areas. This compaction was reflected in height growth reductions of 39 to 59 percent in five-year old loblolly pine (Pinus taeda L.) on decks and primary roads. Number of pine per acre was reduced by 88 to 91 percent on the same areas. Root collar diameters also decreased but were not significantly different from those on relatively undisturbed plots. These results are discussed in relation to the 1 percent proportion of the harvested area involved in soil property impacts and reduced tree growth.


1988 ◽  
Vol 2 (2) ◽  
pp. 191-195 ◽  
Author(s):  
Robert J. Mitchell ◽  
Bruce R. Zutter ◽  
David B. South

Third-year heights, third-year root-collar diameters, and 3 yr volume growth of loblolly pine seedlings were examined in relation to a) root-collar diameter class at time of planting and b) herbaceous weed control. Treatments were a) no weed control and b) complete control for 2 yr. For both weed control treatments, means for third-year heights, groundline diameters, and volume growth were related positively to initial seedling diameter. The influence of initial seedling diameter on third-year diameters and heights did not differ among weed control treatments. However, the influence of initial diameter on volume growth did differ among weed control treatments. Thus, when using herbaceous weed control, additional gains in early volume growth can be realized by planting seedlings with large root-collar diameters.


Genetics ◽  
1999 ◽  
Vol 151 (1) ◽  
pp. 321-330 ◽  
Author(s):  
Mitchell M Sewell ◽  
Bradley K Sherman ◽  
David B Neale

Abstract A consensus map for loblolly pine (Pinus taeda L.) was constructed from the integration of linkage data from two unrelated three-generation outbred pedigrees. The progeny segregation data from restriction fragment length polymorphism, random amplified polymorphic DNA, and isozyme genetic markers from each pedigree were recoded to reflect the two independent populations of parental meioses, and genetic maps were constructed to represent each parent. The rate of meiotic recombination was significantly greater for males than females, as was the average estimate of genome length for males {1983.7 cM [Kosambi mapping function (K)]} and females [1339.5 cM(K)]. The integration of individual maps allows for the synthesis of genetic information from independent sources onto a single consensus map and facilitates the consolidation of linkage groups to represent the chromosomes (n = 12) of loblolly pine. The resulting consensus map consists of 357 unique molecular markers and covers ∼1300 cM(K).


2021 ◽  
Vol 491 ◽  
pp. 119176
Author(s):  
Michael A. Blazier ◽  
Thomas Hennessey ◽  
Laurence Schimleck ◽  
Scott Abbey ◽  
Ryan Holbrook ◽  
...  

1997 ◽  
Vol 21 (3) ◽  
pp. 116-122 ◽  
Author(s):  
Thomas A. Waldrop

Abstract Four variations of the fell-and-burn technique, a system developed to produce mixed pine-hardwood stands in the Southern Appalachian Mountains, were compared in the Piedmont region. All variations of this technique successfully improved the commercial value of low-quality hardwood stands by introducing a pine component. After six growing seasons, loblolly pine (Pinus taeda L.) occupied the dominant crown position and oaks the codominant position in fell-and-burn treated stands on poor to medium quality sites. The precise timing of felling residual stems, as prescribed by the fell-and-burn technique, may be flexible because winter and spring felling produced similar results. Although summer site preparation burns reduced hardwood height growth by reducing the length of the first growing season, they did not improve pine survival or growth. Pines were as tall as hardwoods within four growing seasons in burned plots and within six growing seasons in unburned plots. Additional research is needed to determine the level or intensity of site preparation needed to establish pine-hardwood mixtures over a range of site conditions. South. J. Appl. For. 21(3):116-122.


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