|
|
How to Manage Pests
UC Pest Management Guidelines
Cherry
Armillaria Root Rot (Oak Root Fungus)
Pathogen: Armillaria mellea
(Reviewed 11/09,
updated 11/09)
In this Guideline:
|
|
|
Roots infected with Armillaria
mellea have white to yellowish fan-shaped mycelial
mats
between the bark and the wood. Dark brown to black rhizomorphs sometimes can be seen on the root surface.
All stone fruit rootstocks are susceptible to Armillaria root rot.
The fungus survives on dead roots.
Generally, once a cherry tree becomes infected with Armillaria mellea, it cannot be saved
and should be removed.
Preparation and Timing
for Treatment
Before planting or replanting an orchard site, remove all infected trees,
stumps, and as many roots greater than 1 inch in diameter as possible.
Healthy-appearing trees adjacent to those showing symptoms are often infected also.
Removal of these adjacent trees and inclusion of that ground in the soil fumigation
may be advisable. Infected trees, stumps, and roots should be burned at the
site or disposed of in areas where flood waters cannot wash them to
agricultural lands. Complete eradication is rarely achieved, and retreatment
may be necessary in localized areas. If the soil is wet or if it has extensive
clay layers to the depths reached by the roots, fumigant treatment may not be
successful. The greatest opportunity for eradication occurs on shallow soils
less than 5 feet in depth. Treat Armillaria
from late summer to early fall.
| Common name |
Amount/Acre |
R.E.I.+ |
P.H.I.+ |
| (trade name) |
|
(hours) |
(days) |
|
| When choosing a pesticide, consider information relating to environmental impact. Not all registered pesticides are listed. Always read label of product being used. |
| |
| PREPLANT |
| A. |
METHYL BROMIDE* |
Label rates |
see label |
NA |
| |
COMMENTS: For preplant fumigation. Use allowed
under List of Approved Critical Uses. Before fumigating, dry soil by
withholding water during summer and using cover crops such as sudangrass or
safflower. The drier the soil the better for deep penetration. Deep-till the
area after drying. If the soil is dusty, wait for an early rain before
ripping and fumigation. Ripping a dry soil that is silty can result in large
clods on the surface. Inject methyl bromide 18 to 30 inches deep with chisels
and cover with gas-proof cover. Increasing the dose tends to increase the
depth of penetration, but it cannot be relied upon to penetrate wet soils,
especially if soils are high in clay. Do not remove the cover for at least 2
weeks and aerate 1 month before planting. Fumigants such as methyl bromide
are a source of volatile organic compounds (VOCs) but are not reactive with
other air contaminants that form ozone; methyl bromide depletes ozone.
Fumigate only as a last resort when other management strategies have not been successful or are not available. |
| |
| B. |
METAM SODIUM* |
| |
(Vapam, etc.) |
Label rates |
48 |
NA |
| |
COMMENTS: Apply in winter when soil
moisture is high. Fumigants such as metam sodium are a source of volatile
organic compounds (VOCs) but are minimally reactive with other air
contaminants that form ozone. Fumigate only as a last resort when other management strategies have not been successful or are not available. |
| |
![[Precautions]](/IMAGES/btn-precautions_bul.gif)
![[UC Peer Reviewed]](/IMAGES/logo-ucpeerreviewed.jpg)
UC IPM Pest Management Guidelines: Cherry
UC ANR Publication 3440
Diseases
J. E. Adaskaveg, Plant
Pathology, UC Riverside
J. L. Caprile, UC Cooperative Extension, Contra Costa County
Acknowledgment for contributions to Diseases:
W. D. Gubler, Plant Pathology, UC Davis
B. L. Teviotdale, Kearney Agricultural Center, Parlier
Top of page
|
