General Information


Alamo is a systemic fungicide for use as a flare root injection for prevention and treatment of (1) oak wilt (Ceratocystis fagacearum) of oaks (Quercus spp.), (2) Dutch elm disease (Ophiostroma ulmi) of elms (Ulmus spp.), (3) sycamore anthracnose (Apiognomonia veneta), and (4) leaf diseases (i.e., Venturia inaequalis, Gymnosporangium juniperi-virginianae, Pucciniastrum goeppertianum, etc.) of crabapple (Malus spp.), and (5) laurel wilt: redbay and other lauraceae species (excluding avocado). It is recommended that Alamo be administered by trained arborists or others trained in injection tech¬niques and in the identification of tree diseases.

Notes: The active ingredient in Alamo has been shown to be safe on a wide range of plant species. Before using Alamo on plants or for diseases that are not listed in the Directions for Use, test Alamo on a small scale basis and evaluate for phytotoxicity and disease control prior to widespread use

Correct Location for Injector Placement

The flare root area is the transitional zone between the trunk and the root system. Uptake and distri¬bution of Alamo is more effective when injections are made into the flare roots. In addition, wounds created in the flare root area close more rapidly in comparison to wounds above the flare root area.

Tree Preparation

1. Heavy, thick, or loose outer bark may be carefully shaved to form a smoother injection point and to ensure the operator that the drill hole penetrates through the bark to the xylem.

2. If the flare roots are not clearly exposed, carefully remove 2 to 4 inches of soil from the base of the tree to uncover the top of the flare roots. Brush away loose soil.

3. Drill holes through the bark, into sapwood using a clean sharp drill bit. Drill hole diameter should be adequate to allow insertion of injection tees and formation of air tight contact between active xylem and the delivery point of the injection tees. Generally, a drill hole diameter of 7/32-5/16 inch for elms, sycamores, and crabapples, and 5/16 inch for oaks is appropriate. Follow manufacturer’s instructions for the particular injection device used in the treatment.

Drill hole depth should be adequate to deliver the product into active xylem tissue. Generally, 3/4 inch depth is appropriate, but trees with thick bark may require increased drill hole depth to reach the active xylem layer.

Space injectors 3-6 inches apart around the base of the tree. Do not drill in the valleys between the flare roots or into cankered areas. Drill above these areas into the trunk, then continue again into sound sapwood on the flares.

4. Disinfect the drill bit between trees with household bleach (20% solution), ethanol, or other dis¬infectant. Rinse bit with clean water after disinfecting.

5. Insert into the drilled holes the injection ports (“tees”) which are connected to plastic tubing. The tubing should have inlet and outlet valves.

6. Mix the specified amount of Alamo and water thoroughly in the tank before beginning the injec¬tion treatment.

Tree Measurement

Measure the diameter of the tree using a tree diameter-tape (D-tape) at 4 1/2 feet above the ground. This is the diameter at breast height (DBH). If only a regular tape is available, measure the tree circumference and divide that number by 3.14.

For crabapples, measure the diameter at the point where the tree begins to branch.

Preparation of Injection Solution

Dilute 10 ml of Alamo in up to 1 liter of water per inch DBH.


For pressurized injections, with the outlet valve open, connect the tank to the inlet valve and begin pumping solution until all air bubbles come out of the outlet valve. Direct the solution into a con¬tainer and return the solution to the tank. Shut off the outlet valve. Pressurize tank to 20-30 psi. Check for leaks and gently tap in tees if necessary. Maintain continuous pressure on the injection system until the full amount of solution is in the tree.

After injection is complete, remove injection tees and leave drill holes unplugged. A water flush to cleanse the hole will assist with wound closure. Soil should be replaced around the tree. It is not neces¬sary to treat the drill holes with wound paint or other sealing compounds.

Contact your local extension agent for more details on tree injection. The injection system described is meant as an example; please refer to manufacturer’s instructions when using other types of tree injection systems.


At the initial injection of Alamo, take notes on the level of disease in each tree. Reevaluate disease level in trees at 12-month intervals after treatment for the potential need for retreatment with Alamo. Preventive applications should be considered 12-36 months after the initial injection. Trees in high disease risk areas or high value trees should be evaluated for possible retreatment 12 months after each treatment.

Follow application procedures described above for repeat injections; new drill holes will be needed for subsequent treatments.

Limitations, Restrictions, and Exceptions


Preventive Treatment

Use 10 ml of Alamo in up to 1 liter of water per inch DBH. For trees less than 10 inches DBH, use 6 ml of Alamo per inch DBH. Make applications when the trees are in full leaf and actively growing for control of the next season’s anthracnose development.

See the Product Information section for details on retreatment.