Q. Unfortunately it
appears our kumquat trees may have bacterial blast fungus. Our tree appears
very healthy and has given us a lot of fruit, but we recently noticed sap
coming from the bottom of main branches. What treatment would you recommend?
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| Sam is oozing from the limbs of this kumquat.It sounds crazy but disease stress from management issues can cause sap oozing like this to appear. The KISS rule tells me to look at the soil and watering issues first. |
A. I usually follow the
KISS rules for diagnosing plant problems. Unless we are in a citrus production
area, or there is a history of disease on these trees, I first conclude it’s a
man-made problem. Regardless, we must rule out the simplest reasons first
before we jump to more exotic disease problems.
KISS rules for diagnosing plant problems. Unless we are in a citrus production
area, or there is a history of disease on these trees, I first conclude it’s a
man-made problem. Regardless, we must rule out the simplest reasons first
before we jump to more exotic disease problems.
Root death because soils are kept too wet cause these symptoms
on citrus. For this reason, I assume the trees watered too often or there is a
water drainage problem in the soil surrounding the roots.
on citrus. For this reason, I assume the trees watered too often or there is a
water drainage problem in the soil surrounding the roots.
Simple test if watering too often issues
After the first year of growth, all fruit trees,
including citrus, should be rooted firmly in the soil. A simple diagnostic tool
helps judge whether wet soils should be a concern or not. Move the tree by its
trunk, back and forth, while looking at where the tree enters the soil. The
tree should be firmly anchored in the soil and not move it. If tree roots move
the soil easily, then the soil has probably been kept too wet and the roots
began “drowning” or rotting.
including citrus, should be rooted firmly in the soil. A simple diagnostic tool
helps judge whether wet soils should be a concern or not. Move the tree by its
trunk, back and forth, while looking at where the tree enters the soil. The
tree should be firmly anchored in the soil and not move it. If tree roots move
the soil easily, then the soil has probably been kept too wet and the roots
began “drowning” or rotting.
There is a tendency during hot weather to water fruit
trees more often, even daily. Most fruit trees, including citrus, prefer at
least one day of no watering between watering days. Unless the tree is newly
planted, or planted in sand, never water trees daily. Instead, increase the
minutes on the clock when you do water.
trees more often, even daily. Most fruit trees, including citrus, prefer at
least one day of no watering between watering days. Unless the tree is newly
planted, or planted in sand, never water trees daily. Instead, increase the
minutes on the clock when you do water.
Mulch can add one extra day between irrigations
Anything that shades the surface of the soil during
summer helps tree roots function better. Their primary functions regarding tree
health are the uptake of minerals and water. They do this better, however, if
the surface of the soil is mulched. Woodchips (or even shredded cardboard, shredded
newspaper or straw) lying on the soil surface gives fruit trees one extra day
between waterings during the summer.
summer helps tree roots function better. Their primary functions regarding tree
health are the uptake of minerals and water. They do this better, however, if
the surface of the soil is mulched. Woodchips (or even shredded cardboard, shredded
newspaper or straw) lying on the soil surface gives fruit trees one extra day
between waterings during the summer.
If the soil is not mulched or covered, soils dry quickly
and get hot in our summer sun and heat. When soils are wet, tree roots grow where
there is a good mix of air and water. Unless the soil has been amended quite a
distance from the tree at the time of planting, most of the tiny roots that
feed on water and nutrients grow in the top 6 inches of soil.
and get hot in our summer sun and heat. When soils are wet, tree roots grow where
there is a good mix of air and water. Unless the soil has been amended quite a
distance from the tree at the time of planting, most of the tiny roots that
feed on water and nutrients grow in the top 6 inches of soil.