Toward Sustainable Cultivation of Pinus occidentalis Swartz in Haiti: Effects of Alternative Growing Media and Containers on Seedling Growth and Foliar Chemistry

Abstract

Abstract:Haiti has suffered great losses from deforestation, with little forest cover remaining today. Current reforestation efforts focus on seedling quantity rather than quality. This study examined limitations to the production of high-quality seedlings of the endemic Hispaniolan pine (Pinus occidentalis Swartz). Recognizing the importance of applying sustainable development principles to pine forest restoration, the effects of growing media and container types on seedling growth were evaluated with the goal of developing a propagation protocol to produce high-quality seedlings using economically feasible nursery practices. With regard to growing media, seedlings grew best in compost-based media amended with sand. Topsoil, widely used in nurseries throughout Haiti, produced the smallest seedlings overall. Despite a low water holding capacity and limited manganese, compost-based media provided adequate levels of essential mineral nutrients (particularly nitrogen), which allowed for sufficient seedling nutrition. Seedling shoot and root growth, as well as the ratio of shoot biomass to root biomass, were greater in polybags relative to D40s. Results indicate that economically feasible improvements to existing nursery practices in Haiti can improve the early growth rates of P. occidentalis seedlings.

Repetitive pruning ofSerianthesnursery plants improves transplant quality and post-transplant survival

“…The choice of container traits such as volume or root training ability is one of the most influential nursery decisions for plant growth in the nursery and after transplanting. 30,35,37,38 The use of repeated mild stressors in the nursery to harden the plants may improve post-transplant plant performance. [39][40][41] The use of artificial lighting to manipulate nursery plant growth and biomass allocation may improve transplant quality.…”

The High Cost of the Low-Cost Polybag System: A Review of Nursery Seedling Production Systems

“…Otherwise, nursery personnel may conclude that polybags and/or field soil are superior based on confounding factors [48] and may produce low-quality seedlings in the new system. For example, one study found that shoot and root growth of Pinus occidentalis was greater for seedlings grown in polybags than for those grown in D40 Deepot™ containers, but the comparison was confounded by the polybags having 50% greater volume [49]. Even still, the authors noted that the higher root-shoot ratio of D40 seedlings compared with polybag seedlings was potentially more favorable for dry outplanting conditions.…”

Use of copper in pine nurseries

“…Likewise, applying 1 m of irrigation would add 0.1 kg-Cu ha -1 to a nursery soil when water contains 0.01 mg-Cu L -1 (Table 5). Irrigation water alone can produce pine seedlings with 4 to 12 μg-Cu g -1 in foliage (Walker and Huntt 1992;Hubbel et al 2018). Copper fertilization is not required at nurseries that irrigate using water with 0.02 mg-Cu L -1 since 3.5 L will provide 0.07 mg-Cu per seedling (equivalent to 70 g per million seedlings).…”

“…Approaches used in container nurseries include: (1) apply copper as part of a slow-release fertilizer; (2) apply copper using foliar applications; (3) using both #1 and #2; (4) apply copper to container walls to prevent root spiraling; (5) rely only on irrigation and media to supply copper (Brix and van den Driessche 1974;Rowan 1977;Donald 1991;Walker and Huntt 1992;Urgiles et al 2009;Shalizi 2015;Hubbel et al 2018). In a survey of ten nurseries, seven used method #3 (Starkey et al 2015).…”