Sagos are stately landscape accents, but they can develop a few problems. Sago palm disease will take you through those problems and help you find solutions.
Most of what looks like sago palm disease is really the result of insect damage or a nutrient deficiency.
This sago is suffering from an infestation of Asian scale.
Sago Palm Yellowing
Sago palm trees require micronutrients. They need manganese, magnesium, iron and potassium. If you fail to feed them three times per year with a fertilizer which contains these elements, they may develop deficiency symptoms.
Sago palm yellowing is caused by a lack of manganese. The
new leaves turn yellow, then brown and frizzy. Apply manganese
powder to the soil in the spring and fall. This is more common on acid
soil, so you might try applying lime every year to prevent a recurrence.
Sago Palm Problems
Most sago palm problems have to do with insects. One of my neighbors has mature sagos adorning his landscape. When one of his plants produced offsets he offered me a pup. I gladly accepted.
I placed my new baby in a white urn out on my screen porch where it flourished. For a while...
One afternoon I went out to sit. It was one of those rare days when I wasn't going to work on the plants but just enjoy them. Well, it wasn't to be. My beautiful little sago was dotted--peppered--with fuzzy white mealy bugs. I flew into action.
The first thing I did was carry the urn out into the yard. I set it in the shade of some oaks. I was segregating it to prevent the infestation from spreading to any other plants.
Then I mixed up a spray solution of horticultural oil and water. I saturated the sago palm tree with this in an attempt to suffocate the bugs. A couple of hours later, I went back out and blasted the plant with the hose, knocking the bugs off.
I checked the plant every morning for a week. Every day there were more bugs! I would spray and rinse again and again. The oil wasn't working so I tried using dish washing liquid diluted in water. When this failed, I sprayed the plant with a real insecticide.
No matter what I used, the result was always the same. More little white dots the next day.
Finally, I gave up and barreled the plant. The bugs must have gained too strong a foothold before I spotted them.
Asian Scale on Sago Palms
This is a big problem in Florida, particularly on the west coast, and in Texas. Asian scale (also called white scale because once coated with the insects, the leaf petioles look as if they've been sprayed with fake snow) is more difficult to eradicate than other, more common types of scale.
All scale is hard to kill because the bugs form a hard outer shell during a certain part of their life cycle. Insecticides are unable to penetrate this armor and can only kill the crawlers--insects in the juvenile stage that haven't developed a shell yet. This is why you have to reapply the treatment every few days. To catch newly hatched crawlers before they mature.
It's a labor intensive process which doesn't always work.
Your chances of ridding a sago palm tree of Asian scale are even slimmer. Unlike most other species, Asian scale burrows up to two feet below ground to feed on the plant's roots. It takes scale about six months to kill a sago palm tree.
You have a better chance of saving the tree if you begin treatment in the early stages of an infestation. Check the undersides of the leaves often. That's where a scale infestation will first be evident.
Treat by spraying the plant with a combination of malathion and horticultural oil once a week until you're sure the scale is gone.
Now comes the hard part: You've got to physically remove the dead bugs between treatments. If you don't, any that remain alive--and some will--will use the bodies of the dead to shield themselves from the spray!
How do you remove the dead scale? With a scrub brush or a high pressure hose.
After several treatments, you'll have reduced the number of bugs enough to begin phase two of your attack.
To maintain control, you'll have to apply a systemic insecticide. Bayer Advanced NATRIA MultiInsect Control has been used with success. Timing seems to be the key here. Apply the chemical to new growth in early to mid spring before the leaves expand. Any new insects that feed on the tree after this should be killed by the chemical.
If you are not willing to go to all this trouble, it would be best to destroy the infested tree to keep the scale from multiplying and spreading throughout the neighborhood.
Sago palm disease is usually an insect infestation in disguise. Get rid of the bugs and, most of the time, your sago palm disease will be cured.
More Sago Palm Tree Info:
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