ONA REPORT

published in

THE FLORIDA CATTLEMAN AND LIVESTOCK JOURNAL


January 2014

Brazilian Pepper Battle Plan


For questions or comments regarding this publication contact: Sarah Lancaster

Brazilian pepper (Schinus terebinthifolius) is a perennial shrub or tree native to Argentina, Paraguay, and Brazil that was introduced in Florida as an ornamental plant during the mid-1800s. It has since invaded numerous types of habitat and is commonly found in fencerows and along the banks of waterbodies throughout peninsular Florida and as far north as Duval County. Brazilian pepper is considered one of the most aggressive invasive plants found in Florida because of its rapid growth, vigorous resprouting, prolific seed production, and ability to grow nearly year-round in varying environments. Overcoming a Brazilian pepper infestation is not an easy task and requires a well-designed plan of attack. This article will discuss key considerations for battling Brazilian pepper.

Know your enemy.
Proper identification and knowledge of the plant is critical for any weed management strategy.

Trunk and branches.

    The trunk of a Brazilian pepper plant has gray, smooth bark and is short relative to the total height of the tree, which can be up to thirty feet. It has numerous arching branches that form a dense, tangled mass.
Leaves (Figure 1).
    Mature Brazilian pepper plants have compound leaves that are alternately arranged with a rachis, or central stalk, that is somewhat red in color. Each leaf has three to thirteen leaflets that are arranged opposite of each other (except for the terminal leaflet). Each leaflet is oblong with veins that are pinnately arranged, meaning the veins originate along the length of the midrib. Leaves are hairless, glossy, and evergreen and may have finely toothed margins.

Flowers and fruit (Figure 2).
    Brazilian pepper is a dioecious plant, meaning male and female flowers are on separate plants. It is difficult to tell the difference between male and female flowers, because they have similar structures. The flowers are white with five petals and arranged in a panicle. Panicles can develop both in the leaf axils along the stem and at the end of the branch. In Florida, Brazilian pepper flowers in September to November and female flowers produce bright red fruits that mature by December. Flowers are insect-pollinated and seeds are dispersed by birds and other animals. Seeds typically germinate between November and April.


Choose your offensive strategy.
There are multiple methods available to control Brazilian pepper;however, most require multiple treatments. The best method for a situation depends on the time of year and location of the plant. Often, an integrated approach that utilizes multiple control methods is most effective.

Mechanical.

    Mechanical control of Brazilian pepper is difficult due to its ability to resprout from stumps and roots. Successful control of Brazilian pepper using mechanical removal requires that the entire plant – including the root system be removed to prevent resprouting. Plants can resprout from roots as small as ¼ inch in diameter. Fire will destroy seeds and prevent the emergence of some new Brazilian pepper plants, but established plants will resprout.
Chemical.

    Multiple herbicides are available to control Brazilian pepper. These herbicides can be applied either to foliage, to the bark, or to cut stumps. Herbicides commonly used include glyphosate, imazapyr, and triclopyr. In addition, Brazilian pepper control with aminocyclopyrachlor, a new active ingredient that should be available in the near future, is being tested. With any herbicide application, it is important to read and follow the label’s instructions. Additional comments about each method are provided below.

    Foliar applications are especially effective for seedlings and are best suited for areas in which thorough foliar coverage is possible and damage to non-target species can be tolerated. It is advisable to wait for one year following cutting brush before applying herbicides. When spraying foliage, the best technique is to spray until the leaves are wet, but no herbicide solution is running off of the leaves. Recommended application rates for some herbicides are listed in Table 1.

    Table 1.  Herbicides and their application rates commonly used for foliar application to Brazilian pepper.


    Active ingredient

    Trade name

    Rate

    Comments

    Glyphosate

    Roundup, Aquaneat, others

    5-8% solution

    Some products may be applied directly to water. 

    Imazapyr

    Arsenal

    1-5% solution

    Should only be applied by licensed applicators. A nonionic surfactant (0.25%) is required.

    Triclopyr

    Garlon, Remedy

    4-8% solution

    Some products may be applied directly to water.

    Basal bark applications are suitable for controlling Brazilian pepper plants that are less than six inches in diameter, require less herbicide per tree than foliar applications, and reduce the risk of injuring non-target species. For a basal bark application, spray the trunk approximately 12 – 18 inches from the ground with a mixture of triclopyr and penetrating oil (Pathfinder is a triclopyr plus penetrating oil mixture formulated for basal bark applications that is applied without further mixing). Do not girdle the tree, as this may reduce the movement of the herbicide in the plant. It may take several weeks for herbicide injury to appear. In general, the best time for basal bark applications is in the fall of the year, when the rate of translocation throughout the plant is greatest.

    Cut stump applications are a combination of mechanical control and chemical control that may provide better control of large Brazilian pepper plants, but are time consuming, given the tendency of Brazilian pepper to produce multiple stems. In a cut stump application, the tree is sawed off as close to the ground as possible and herbicides are applied to the stump to reduce resprouting. It is best if the herbicide is applied immediately (within 5 minutes) after cutting and removal of the sawdust. If this is not possible, basal oil should be mixed with the herbicide. For larger stumps, it is only necessary to treat the outer edge, as this is the only part of the plant that is living and will translocate the herbicide to the roots. Applying herbicide to the entire stump increases the amount of herbicide used, but does not increase control. It is appropriate to treat the entire surface of a small (less than three inches in diameter) stump. The best time to cut Brazilian pepper is when they are not producing fruit, to prevent spreading seeds when the plants are removed. Application rates are listed in Table 2.

    Table 2.  Herbicides and their application rates commonly used for cut stump application to Brazilian pepper.


    Active ingredient

    Trade name

    Rate

    Comments

    Glyphosate

    Roundup, others

    50-100% solution

    Glyphosate should not be applied with basal oil. If stumps cannot be treated immediately after cutting, do not use glyphosate. 

    Imazapyr

    Arsenal AC, Stalker

    6 oz Arsenal/ gallon,
    8-16 oz Stalker/gallon

    Should only be applied by licensed applicators.

    Triclopyr

    Garlon 3A

    50-100% solution

    Garlon 3A does not mix effectively with basal oils.  If stumps cannot be treated immediately after cutting, do not use Garlon 3A. 

    Triclopyr

    Garlon Ultra, Remedy Ultra

    25% solution in
    water or basal oil

     

Sometimes, the best offense is good defense. The best way to manage Brazilian pepper is prevention. Be alert to germination of new seedlings and take measures to remove the plants before they become well established. It is important to scout previously infested areas annually and treat them as needed to avoid reinfestation. If you are using mechanical control as part of your management plan, be sure to take steps to avoid spreading fruits and seeds on the trees you remove. You can also help inform others about the consequences of cultivating Brazilian pepper and the Florida laws that prohibit its sale or transport.