Rosette is caused by zinc deficiency in pecan trees and is characterized by yellowing and narrowing of leaves, as well as inhibited new shoot growth. It can be corrected by spraying zinc sulfate on leaves and applying it to the soil. Internal breakdown causes the inside of almost mature nuts to become soft and watery in late summer. The cause is unknown but it affects certain varieties like Moneymaker and Mahan more severely. Spanish moss can accumulate enough in pecan trees in southeastern coastal areas to increase damage from ice and wind. It does little harm at low levels but can be sprayed with copper sulfate during dormancy when thick enough to cause problems.

2. Pecan nut Physiological Disorders
A
Lecture To ToT trainees ( FFS)
By
Mr. Allah DadKhan
Provincial Coordinator IPM KPK
MINFAL Pakistan

3. Rosette and Bunch
 Rosette occasionally occurs on pecans in North Carolina.
This problem is caused by zinc deficiency or by certain soil
types where zinc is unavailable to pecan trees. Initial
symptoms occur mostly on the branches in the top of the
tree. Leaves are yellowish and mottled. In advanced
stages, leaflets become narrowed and crinkled on lower
branches. New shoot growth is inhibited. Eventually twigs
and branches die back from the tips. Zinc deficiency can be
corrected by spraying the leaves twice with zinc sulfate
alone or added to other sprays at the rate of 2 pounds per
100 gallons of water (1 tbsp per gallon). The zinc also may
be applied to the soil around trees by spreading the
material from near the trunk outward to the drip line. A soil
test is desirable to determine the amount of zinc required
but in general can be applied at the rate of 1/2 pound for
each inch of trunk diameter

4. Internal Breakdown
 Internal breakdown of almost mature nuts
in late summer occurs each year. The
inside part of the nut becomes soft and
watery. This is a physiological disorder the
cause of which is not known. Its severity
varies from year to year, but appears to
be most prevalent on certain varieties
such as Moneymaker and Mahan.

5. Spanish Moss
 In southeastern and coastal areas,
Spanish moss can occasionally become
thick enough in pecan trees to increase
ice and wind damage. A small amount of
Spanish Moss does little or no damage to
trees. Where it is a problem, spray the
moss with copper sulfate at the rate of 10
pounds per 100 gallons (6 tbsp per
gallon) during the dormant season