Pecan trees respond rapily and favorably to foliar applications of Multi-K™. Growers and researchers have observed a wide range of benefits.
Pecan trees benefit from Multi-K™:
♦ Better shoot growth ♦ Enhances absorption of zinc and other micronutrients
♦ Prevents leaf scorch ♦ Increases K level in leaves
♦ Improves nut quality ♦ Increases kernel oil content
♦ Boosts yield ♦ Helps offset irregular bearing
The importance of foliar feeding
Insufficient K supply:
The uptake of potassium by roots and the tree depletes K reserves which are needed by the fruit during its rapid fruit en!argement stage. Any reduction of K supply during this period causes a deterioration of fruit quality.
Rapid response to Multi-K™ Spray:
Pecan trees often respond very slowly to potassium when applied to the soil, requiring up to 5 years before leaf K concentrations are increased.
Foliar feeding with Multi-K™ allows K deficiencies to be corrected during the year of its application since it increases potassium concentration in the leaf and, subsequently, the nut yield.
Irregular Bearing:
Fruiting reduces potassium concentration in. the leaves and can be one of the causes of irregular bearing.
The following table shows a significant depletion in potassium in the leaflets from "Stuart" pecan trees during the "On" vs "Off" cycles of irregular fruiting. (W aycross, GA, USA):
Fruiting Cycle | Level In Leaflets | |
N% | K% | |
Off | 3.14 | 1.67 |
On | 3.17 | 1.36 |
Foliar application with Multi-K™ supplies the essential potassium at the stage when it is needed for fruiting.
What is Multi-K™?
Multi-K™ is potassium nitrate (KN03), a fully water-soluble fertilizer composed solely of plant nutrients: 13% nitrogen in nitrate (N03-) form and 46% potash (K20) or 38% K. Foliar applications of this high-K ferti!izer can rapidly correct
potassium deficiency and aid in other K related benefits.
General:
Pecan trees are very inefficient in absorption of K from the soil. Augmenting a regular fertilization program with supplemental foliar applications of Multi-K™ can help correct K shortages by increasing the K level in leaves. This results in an ample supply of potassium for enhancement of nut yield, nut quality and kernel oil content.
Rate:
Multi-K™ should be applied as a 0.5% to 1.0% spray solution.
Apply the low concentration on young foliage. Some varieties may be susceptible to high Multi-K™ cסncentrations.
To assess, see "Compatibility" paragraph. Spray until there is whole tree run-off.
Time of applications:
The first Multi-K™ application should be sprayed with the second pre-pollination treatment. Subsequent applications should accompany each pesticide spray.
Number of applications:
Linked to the frequency of and combined with pesticide sprays. An average of 5-8 treatments per growing season, depending upon number of pesticide sprays.
Compatibility:
Multi-K™ is compatible with most pesticides used for pecan. It is also compatible with urea (feed grade) and
micronutrients such as zinc; however it is advisable to confirm compatibility by mixing a sample of the spray materials at the recommended concentrations before adding to the tank mix. It is also recommended that this mixture be sprayed on few branches prior to actual treatment in order to assess whether there wil be any adverse effect.
Adjuvant surfactant:
When applying with pesticides, a pH of 5-6 should be maintained.
An acidifying surfactant should be added to prevent alkaline hydrolysis of pesticides and to assure nutrient absorption. Read surfactant label for best results.
Mixing:
Add Multi-K™ when spray tank is one-third full of water, then add other spray materials. Mix by agitation.
Suspetibility:
High temperature and low humidity may increase the susceptibility of pecan trees to spray injury. Preferred time for spraying is early morning or evening. Trees under stress conditions should not be sprayed.
The effect of nitrogen and potassium
Nitrogen (N):
Pecan trees respond to nitrogen application with enhanced tree appearance, shoot growth and an increase in the number of new shoots - all factors which are important to production.
Nitrogen is also important because yield generally increases as the N level in leaves increases.
Potassium (K):
The optimization of K levels in leaves generally increases shoot growth, nut yield and edible kernels.
Leaves serve as potassium reservoirs for fruit growth. By building up the K content prior to rapid fruit growth,
fruit-induced K stress in the leaves can be prevented; thus, preventing leaf scorch and premature leaflet drop off.
This is illustrated by nitrogen and pc,tassium levels in leaflets of "Chickasaw" pecan on two sampling dates as shown below (dry weight basis):
Sampling Date |
Level in leaflets | |
N% | K2O% | |
July 15 | 2.60 | 0.77 |
Sep 22 | 2.19 | 0.48 |
The reduction of nutrients in the leaf is primarily due to the large accumulation of potassium in the shuck and nitrog,)n in the kernel, as presented in the following table ("Chickasaw'', Albany, Georgia, USA; September 22, 1977; dry weight basis):
Tissue | N | K | ||
% | mg/fruits | % | mg/fruits | |
Shuck | 0.84 | 190 | 4.73 | 1053 |
Shell | 0.43 | 35 | 0.31 | 74 |
Kernel | 1.73 | 504 | 0.41 | 113 |