Southern Tablelands Farm Forestry Network |
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[Print this fact sheet - pdf 91kb] Once the weeds are under control, it is important to make sure the newly planted trees receive an adequate amount of fertiliser. There is no point fertilising the trees if there has been no or inadequate weed control. Fertilising with weeds present will only result in strong and healthy weeds causing the trees to either not survive or have reduced growth. Timing The seedling should be in active growth phase when fertiliser is applied, so that it can make best use of it. If the tree is not actively growing a large percent of the fertiliser will be lost into the system through volatilisation. Therefore the best time to apply the fertiliser is generally Spring or just following planting. The trees should be just beginning to establish in warm, moist soil with good weed control when fertiliser is applied. Application method Fertiliser around the trees needs to be placed close enough to allow the tree to gain access to it however, far enough away from the stem to ensure there is no burning of the foliage. This equates to approximately 30cm (12 inches) from the stem. The simplest way to apply fertiliser is through the use of a cup and bucket, ensuring that the size of the cup is consistent with the appropriate quantity of fertiliser to be applied to each tree. Alternatively transparent cups with a line determining the necessary fertiliser amount can be used. Note that different fertilisers take up different volumes for the same weight. Fertiliser should be placed in two semi-circles around the tree. The semi-circles should be placed either side of the tree as apposed to above and below the tree where there is a slope. The problem with the above and below placement is that rain can wash the fertiliser placed above the tree to around its stem causing possible burning damage. The fertiliser placed below the tree could be washed away, out of reach of the roots. Pine plantations The most commonly used fertilisers for pine plantations are the standard “forestry mixes” (@ 150gms/tree) available from rural supply stores. Soils in the Southern Tablelands are generally poor in Nitrogen and Phosphorus and therefore application of both is necessary. Application of Phosphorus is less important if you think your site is fertile. In pines Phosphorus promotes root growth and Nitrogen promotes shoot growth. Soils in the Southern Tablelands are also commonly deficient in Boron, which is a trace element essential for good pine development. Boron deficiency in pine trees will not be exhibited until the second or third summer after planting, when the browning off of the growing tip will be the first sign. If the deficiency is severe and goes uncorrected then the dieback, re-shooting and subsequent poor form that results, may render the plantation useless for commercial purposes. Application is best conducted in the second year after planting, in the Summer months when weeds have dried off. Natives plantations Generally native plantations can benefit from chemical fertiliser application, using N:P:K mixes low in Phosphorus. Fertiliser application may not be necessary on ex-pasture sites. Consider the amount of stock manure as well as the history of the paddocks fertiliser application prior to fertilising a new plantation. Fertilisers are available in general use and slow-release form from rural supply stores. Application rates vary between brands. Native plantations also respond well to the application of organic matter, in addition to or instead of chemical fertilisers. Apply organic matter generously around freshly planted seedlings, making sure that the ground surface is well covered, yet not chocking the young stem. Organic matter not only adds nutrients but also reduces soil evaporation. Mulched and composted material is best, although grass slashings thrown up on planted mounds from adjacent row spaces is also beneficial. Be careful not to use large quantities of fresh manure or manure high in phosphorus, such as poultry. |