Q.
I have 19 mature, healthy Mexican fan palms pruned every year after flowering.
This year they were pruned on June 13 but after three weeks one suddenly died,
and another died two weeks later. I used the same pruning crew for 5 years with
no problems. I removed about 250 square feet of turf from in front of the trees
last year with no other significant changes to their irrigation or
fertilization regimen.
I have 19 mature, healthy Mexican fan palms pruned every year after flowering.
This year they were pruned on June 13 but after three weeks one suddenly died,
and another died two weeks later. I used the same pruning crew for 5 years with
no problems. I removed about 250 square feet of turf from in front of the trees
last year with no other significant changes to their irrigation or
fertilization regimen.
A.
They died because the central bud at the top of the tree died. I can’t tell you
exactly the reason why they died without climbing to the top, but I can give
you some possibilities. Perhaps you can sort it out from there.
They died because the central bud at the top of the tree died. I can’t tell you
exactly the reason why they died without climbing to the top, but I can give
you some possibilities. Perhaps you can sort it out from there.
I don’t think this is an irrigation
issue because it happened too rapidly. It is most likely a disease problem. I
would guess it is either from using unsanitary pruning tools or too many palm fronds
were removed.
issue because it happened too rapidly. It is most likely a disease problem. I
would guess it is either from using unsanitary pruning tools or too many palm fronds
were removed.
Sanitation a Problem
Pruning tools must be sanitized to
prevent the transmission of disease from one tree to another. Diseases are passed
from tree to tree or even limb to limb by using unsanitary tools. At a bare
minimum, pruning tools should be sanitized between job sites. Ideally, they
should be sanitized between trees, particularly when pruning “sick” trees.
prevent the transmission of disease from one tree to another. Diseases are passed
from tree to tree or even limb to limb by using unsanitary tools. At a bare
minimum, pruning tools should be sanitized between job sites. Ideally, they
should be sanitized between trees, particularly when pruning “sick” trees.
 |
| 70% ethyl alcohol is probably the best sanitizers but a good cleanser will work |
I like to ask, “Would you let a
doctor use a needle or scalpel just used on another patient?” Pruning plants is
similar. Disease transmission is less likely between plants that are not
similar but when plants are similar, all palms for instance, more care should
be used.
doctor use a needle or scalpel just used on another patient?” Pruning plants is
similar. Disease transmission is less likely between plants that are not
similar but when plants are similar, all palms for instance, more care should
be used.
Sanitation of pruning tools can be
simple; from wiping the tools clean and applying alcohol for Pine Sol or even heating
the blade with a Bic butane lighter.
simple; from wiping the tools clean and applying alcohol for Pine Sol or even heating
the blade with a Bic butane lighter.
Too Many Fronds Removed
The second possibility is damage to the
central bud by removing too many fronds protecting it. The central bud of a
palm tree is located at the very top of the trunk. It is surrounded by palm
fronds that emerged from the bud earlier in the season.
central bud by removing too many fronds protecting it. The central bud of a
palm tree is located at the very top of the trunk. It is surrounded by palm
fronds that emerged from the bud earlier in the season.
 |
| Removing too many fronds can leave the central bud exposed to intense sunlight and brutal wind, the bud dies and the tree collapses. |
The newest fronds are clustered
around the bud while older fronds are lower and removed as they become brown or
drop below horizontal. Older fronds provide no protection to the bud. Horticulturists
all agree that excessive removal of palm fronds can lead to palm problems.
around the bud while older fronds are lower and removed as they become brown or
drop below horizontal. Older fronds provide no protection to the bud. Horticulturists
all agree that excessive removal of palm fronds can lead to palm problems.
Excessive removal occurs when fronds
are removed that previously played a role in shading it from intense sunlight
or protection from other types of damage. If too many fronds are removed,
protection of the bud is jeopardized.
are removed that previously played a role in shading it from intense sunlight
or protection from other types of damage. If too many fronds are removed,
protection of the bud is jeopardized.
 |
| Too many fronds removed? Duh!!!! This is exaggerated but it was done! Leave a half-moon of fronds when you are done. |
How many should remain after pruning?
Enough to protect the bud and provide energy through the leaves for vigorous new
growth. Remaining fronds should occupy an upside down half-circle or 180°.