Q.
The leaves on my fig tree appear burned after this rain. I foliar sprayed it
with Neem oil and soap and fish protein isolate, These trees were planted last
fall and mulched with 1 foot of woodchips and looked amazing until now. They
are watered three times each week in the summer.
The leaves on my fig tree appear burned after this rain. I foliar sprayed it
with Neem oil and soap and fish protein isolate, These trees were planted last
fall and mulched with 1 foot of woodchips and looked amazing until now. They
are watered three times each week in the summer.
A.
The leaves do look like they are diseased. But I have a saying, “When the top
looks bad, look at the ground.” First eliminate the easy problems before
jumping to more difficult ones.
The leaves do look like they are diseased. But I have a saying, “When the top
looks bad, look at the ground.” First eliminate the easy problems before
jumping to more difficult ones.
I wonder if that 12 inches of
surface mulch is rotting the trunk of the tree. It is easy to kill young trees
if they sink, the bottom of the trunks buried in dirt, into the planting hole
after planting. Or if woodchip mulch on the soil surface is piled against the
trunk and kept wet.
surface mulch is rotting the trunk of the tree. It is easy to kill young trees
if they sink, the bottom of the trunks buried in dirt, into the planting hole
after planting. Or if woodchip mulch on the soil surface is piled against the
trunk and kept wet.
In both cases wet soil or wet mulch
against the trunk can cause a disease called “collar rot”. The disease rots the
trunk and “chokes” the top of the tree. When this happens, leaves look diseased
or as if the plant isn’t getting enough water. This becomes very apparent
during hot weather.
against the trunk can cause a disease called “collar rot”. The disease rots the
trunk and “chokes” the top of the tree. When this happens, leaves look diseased
or as if the plant isn’t getting enough water. This becomes very apparent
during hot weather.
Start on your knees and pull the
mulch away from the trunk. Keep it there permanently, 6 to 12 inches away. Next,
carefully remove the soil from around the trunk until you find tree roots
coming from the trunk growing horizontally.
mulch away from the trunk. Keep it there permanently, 6 to 12 inches away. Next,
carefully remove the soil from around the trunk until you find tree roots
coming from the trunk growing horizontally.
If this small area of the trunk
looks water soaked, there might be a problem. I will take a small penknife and
cut away a narrow strip of the trunk that was buried in soil and mulch. The
wood under the strip should be white or greenish white.
looks water soaked, there might be a problem. I will take a small penknife and
cut away a narrow strip of the trunk that was buried in soil and mulch. The
wood under the strip should be white or greenish white.
If there is more than ½ inch of soil
covering the trunk, or the trunk was buried in wet mulch, the tree may develop
collar rot. All you can do is let the covered part of the trunk air dry and
hope for the best.
covering the trunk, or the trunk was buried in wet mulch, the tree may develop
collar rot. All you can do is let the covered part of the trunk air dry and
hope for the best.
I have seen collar rot develop on the
lower trunk young figs and pomegranate that are buried. Most figs and
pomegranates are grown on their own roots. If the top of the tree dies, wait a
couple of months and see if anything suckers from the roots or base of this
tree. If it does, don’t replace the tree.
lower trunk young figs and pomegranate that are buried. Most figs and
pomegranates are grown on their own roots. If the top of the tree dies, wait a
couple of months and see if anything suckers from the roots or base of this
tree. If it does, don’t replace the tree.
These basal suckers will grow very
rapidly into a new tree because the tree already has established roots. When
one of the suckers is 12 inches tall, remove the others for a single trunk tree
or select 3 to 5 for a multi-trunk tree.
rapidly into a new tree because the tree already has established roots. When
one of the suckers is 12 inches tall, remove the others for a single trunk tree
or select 3 to 5 for a multi-trunk tree.
It’s possible these leaf problems
are related to a leaf disease but I don’t recognize it. Sometimes when dead
areas develop from disease pathogens, the dead area of the is bordered by
yellow. This yellowing is where the plant tissue is still dying. Sometimes this
yellowing doesn’t exist but only because the disease has stopped spreading.
are related to a leaf disease but I don’t recognize it. Sometimes when dead
areas develop from disease pathogens, the dead area of the is bordered by
yellow. This yellowing is where the plant tissue is still dying. Sometimes this
yellowing doesn’t exist but only because the disease has stopped spreading.
The humidity in Las Vegas is
unusually high right now because of the so-called “summer monsoon” and rains. I
expect diseases to pop up during this kind of weather. Having leaf diseases on
fruit trees would not be uncommon during this time of year.
unusually high right now because of the so-called “summer monsoon” and rains. I
expect diseases to pop up during this kind of weather. Having leaf diseases on
fruit trees would not be uncommon during this time of year.
Instead of spraying, driving using a
passive approach towards controlling diseases. Remove extra leaves that might
be blocking the movement of air and wind through the canopy. As you see leaf
diseases, remove the infected leaves and dispose of them. The plant will grow
new leaves in places where there is sunlight. Leaf diseases slow down or stop
as the weather changes.