ke.gardens-tricks.com
Miscellaneous

Scotch Broom Control: Getting Rid Of Scotch Broom Shrub From The Yard

Scotch Broom Control: Getting Rid Of Scotch Broom Shrub From The Yard


We are searching data for your request:

Forums and discussions:
Manuals and reference books:
Data from registers:
Wait the end of the search in all databases.
Upon completion, a link will appear to access the found materials.


Though sometimes attractive in the landscape, the scotch broom shrub (Cytisus scoparius) is a noxious weed in the Northwestern U.S. and responsible for the loss of a good deal of that areas’ timber income due to crowding out native species. Scotch broom control is difficult and often time-consuming, but worth the effort to get rid of scotch broom in the yard and forest.

Scotch broom shrub was introduced as a landscape ornamental as early as the 1800’s, then used extensively for erosion control in public landscapes, such as roadside plantings, but quickly became a nuisance. Once established, it is difficult to kill scotch broom.

Scotch Boom Identification

Scotch broom is a deciduous shrub that can be found on the edges of wooded areas and in open fields. It is an aggressively invasive plant that will grow thickly rather quickly.

Scotch boom has tear-shaped leaves that grow in groups of three and mostly bright yellow flowers with occasional purple and red flowers mixed in. The flowers grow in clusters along the length of the stems. When in flower, the entire bush appears to be yellow.

After flowering, scotch broom will produce several dozen large pods that contain hard brown seeds.

Reasons to Kill Scotch Broom

Effects of scotch broom shrub include competition with native forest plants. In addition, the scotch broom shrub produces soil conditions which encourage growth of other non-native weeds, choking out native foliage.

Wildlife find the shrub unpalatable and may be driven from a habitat overtaken by the scotch broom. Preserving native habitats is an important reason to get rid of scotch broom.

Information on Scotch Broom Control

Scotch broom control may be mechanical, shearing to the ground by hand or with machinery. Mechanical scotch broom control requires repeated shearing with a chainsaw or trimmer. The roots form a dense and returning mass so this may have to be done repeatedly to kill the plant.

Root removal is often best carefully done by hand in the home landscape. Make sure you get all of the roots, as partial removal of roots will it to come back instead of fully getting rid of scotch broom.

Controlling scotch broom in the home landscape may be best accomplished by continual shearing during the driest seasons. Be mindful of new sprouts, which will quickly establish themselves and remove these as they appear.

Spread mainly by prolific seed production and dispersal, it is difficult to kill scotch broom in the long term because of the seeds. The hard-coated seeds remain viable for as long as 80 years.

Mechanical removal with large tillers and plows often does not work well with controlling scotch broom, and encourages re-growth. Scotch broom shrubs most often overtake areas where soil had been disturbed, as by tilling. Broad spectrum herbicide control is somewhat successful, but must be applied before flowers emerge.

Biological controls, such as a species of seed weevil, are under experimentation and found to be successful at reducing seed spread in Oregon. Larvae of the weevil enter seedpods and are estimated to eat 80% of the seed before they can disperse. Check inside seed pods before treating with chemicals. Larvae should not be destroyed, as they appear to be the best resource for controlling scotch broom invasions.

Note: Although broom plants produce attractive, sweet-pea like blooms, they have become highly invasive in many areas. It is important to check with your local extension office before adding the plant or its relatives to your landscape to see if allowable in your area.


Thank you for doing your part to control scotch broom in Kitsap!

For more homeowners, the best way to control it is still to dig the large plants out, and in fact, "weed wrenches" work great for helping to pry out the deep roots of older, established scotch broom plants. Our WSU Kitsap Extension office loans out the weed wrenches, and you can learn more about it by contacting Lisa Rillie at [email protected]

As far as disposal, our Kitsap Noxious Weed Program has a voucher that is available to landowners for disposing of noxious weeds in Kitsap County landfills for free by the bag or by the load. To learn more about the voucher, noxious weed bags and what facilities and weeds they can be used for, please contact Lisa Rillie at [email protected]

Once the large plants are removed, regular mowing of an area once covered in scotch broom can help keep down new seedlings. If you can prevent the plants from blooming every year, you will help reduce the number of seeds that are produced and thus, the number of plants that can pop up later. If the area has been overgrown with scotch broom for many years, there may be many, many seeds in the soil, ready to sprout at a later date.

A patient outlook is needed, but don't despair, scotch broom can be controlled using a variety of tactics over time. To learn more about some of these tactics, visit our Noxious weed pages of our website at the following link:http://ext100.wsu.edu/kitsap/nrs/noxious/resources/ You'll see there is a pdf that you can download on Scotch Broom, it's impacts and how to control it.

Best of luck to you and thank you again for helping to control noxious weeds in Kitsap!


How to Manage Pests

Brooms

French broom invading a hillside near Bodega bay, California.

Brooms are a group of shrubs that were introduced into North America from Europe and North Africa in the mid-1800s. Brooms can be found growing along roadsides, forestlands, coastlines, riparian areas, brushlands, and disturbed areas. Initially introduced as ornamentals, they were later promoted by federal and state agencies for erosion control along roadsides and in mined areas. As a result, five broom species have become naturalized in California and are classified as invasive weeds by many federal, state, and local jurisdictions.

These highly competitive shrubs grow rapidly and form dense stands that both people and wildlife find impenetrable. Their dense stems make regeneration of most other plant species difficult or impossible, and they create a dangerous fire hazard. In addition, as legumes, brooms can fix atmospheric nitrogen, increasing soil fertility and giving a competitive advantage to other non-native weeds that, unlike the local natives, thrive on high nitrogen levels.

The four most common broom species in California are Scotch broom (Cytisus scoparius), French broom (Genista monspessulana), Spanish broom (Spartium junceum), and Portuguese broom (Cytisus striatus).

Although many retailers have stopped selling the species mentioned above, some nurseries still sell these and other brooms, including many hybrids. Residents should avoid planting them as many of these have similar invasive characteristics. Some of the available species include sweet broom (Cytisus x spachianus and Genista racemosa) and multiple Scotch broom hybrids including Burkwood’s broom (Cytisus x burkwoodii), Lilac Time, Moonlight, and Lena to name a few.

The safest approach is to avoid planting any broom species. Several alternate plant species have similar attributes but are not invasive. Contact your county UC Master Gardener office or visit PlantRight.org for a list of recommendations (See RESOURCES).

IDENTIFICATION AND BIOLOGY

Brooms are upright shrubs that grow 3 to 10 feet tall. They generally produce bright yellow, pea-shaped flowers from April to June.

Scotch and Portuguese brooms produce their flowers in the leaf axils, while French and Spanish brooms have flowers at the branch tips. The flowers of French broom are substantially smaller than those of the other three common species. In some areas, Scotch broom flowers can be multicolored, with red or purple spots or petals. Bridal veil broom (Retama monosperma) is a white-flowered broom that has become invasive in parts of Southern California.

Stem shape can be used to distinguish between broom species. Scotch broom has a 5-angled stem (star-shaped when viewed in cross-section), French and Portuguese have an 8- to 10-angled stem, and Spanish broom has a finely ribbed stem, making it nearly round.

Leaf characteristics also identify the species. Spanish broom produces simple leaves, while the other three species have mostly trifoliate leaves. For most species, new leaves produced in spring are often lost during hot, dry summer months or periods of stress, giving the plants their characteristic whisk-broom appearance. Scotch, Portuguese, and Spanish brooms are deciduous while French broom is an evergreen. Table 1 shows identifying features of these four broom species.

All four broom species produce dark colored pods in mid- to late summer that contain shiny greenish-brown seeds. Invasion and spread of brooms are entirely driven by seed dispersal.

The pods ripen during the dry summer months, then explosively eject their seeds several feet away, making a popping noise audible for some distance. All brooms are prolific seed producers, with a single shrub producing as many as 2,000 to 3,500 pods containing up to 20,000 seeds.

Between 30% and 60% of seeds are expected to germinate the first year, with the rest staying dormant and germinating at lower rates in subsequent years. Germination rates vary across species, sites, and years. Under most conditions, the majority of new seedlings die, but even so, the large number of seeds produced by a single plant can result in many seedlings. The seeds have an impervious seed coat, enabling some seeds to remain dormant in the soil for decades and making long-term management difficult.

After germination, growth of seedlings for the first two years can be slow, such that people sometimes do not recognize that they have a broom problem until it is several years along. At that point, or sometimes earlier, growth becomes very rapid—with plants growing as much as 3 or 4 feet in one year. Rapid growth continues for another 3 to 4 years, followed by 6 to 8 years of relatively slow growth. Next is a period of senescence, with more dead woody tissue than green. Plants typically live 12 to 17 years but can survive for as long as a quarter-century.

In established broom stands, seeds often remain dormant until older plants are removed or soil disturbance occurs, at which point a carpet of seedlings will appear. Brooms don’t usually reach flowering maturity until the second or third year of growth, which allows for targeted removal of established shrubs first, followed by seedlings and younger plants thereafter.

Distinguishing Features of Four Common Broom Species in California.
Scotch broom
(Cytisus scoparius)
French broom
(Genista monspessulana)
Spanish broom
(Spartium junceum)
Portuguese broom
(Cytisus striatus)

Stems: 5-sided star-shaped cross section
Leaves: compound, 3 leaflets, deciduous, sometimes single on new twigs

Stems: 8 to 10 ridges nearly round cross section.
Leaves: compound, 3 leaflets, evergreen, usually dense

Stems: smooth or finely ribbed round cross section
Leaves: simple, deciduous, sparse

Stems: 8 to 10 ridges nearly round cross section
Leaves: compound, 3 leaflets, deciduous, sometimes single on new twigs

Flowers: single or paired in leaf axils
Petals: yellow or partially red

Flowers: 4 to 10 in clusters at end of short branches
Petals: yellow

Flowers: several in open racemes at branch tips
Petals: yellow

Flowers: single or paired in leaf axils
Petals: yellow

Seed pods: flattened, only margins hairy

Seed pods: slightly flattened, entirely covered with long hairs

Seed pods: slightly flattened with few, if any, long hairs

Seed pods: slightly inflated, entirely covered with long hairs

MANAGEMENT

The two primary methods for managing brooms are mechanical removal and treatment with herbicides (weed killers). Broom establishment is through seed dispersal, so maintaining a healthy cover of desirable vegetation and reducing soil disturbance may reduce the potential for broom invasion. Ongoing monitoring for new seedlings is crucial for successful management.

Mechanical Control

Small infestations can be removed by hand-pulling or mechanical grubbing. A variety of tools can aid in removal, including shovels or picks, chains, or specialized tools such as the Brush Grubber or The Uprooter. It is easiest to remove plants in early spring or late fall when the soil is moist and roots can be dislodged. Grubbing when the soil is dry and hard usually will break off the stems, leaving rootstalks that may resprout. Fortunately, with brooms, fragments of stems do not survive to produce new roots as in some weedy species.

Mowing broom plants gives poor control unless performed repeatedly throughout the growing season. Within a couple months of germination, young plants usually have produced underground rootstocks large enough to recover from a single mowing. Use extreme caution when mowing during spring and summer because of the potential for wildfires. Mowing later in the season also can spread seeds.

Lopping mature plants near the base will provide some control if done when plants are moisture-stressed in late summer, or in late spring following a winter with little rainfall. Lopping at other times can lead to vigorous resprouting.

Under most conditions in California, brush rakes and bulldozers that leave pieces of rootstocks behind do not provide successful control. In some cases, brush removal in late summer, when plants experience moisture stress, can slow their ability to recover. However, using large equipment to clear land may also promote seedling establishment, making follow-up control essential.

Cultural Control

Burning alone is generally not an effective method for controlling brooms. Although burning can remove large amounts of debris, it can also increase the broom population, as it removes competitive vegetation and releases nutrients into the soil. A very hot burn will kill seeds, but a cooler burn will stimulate the germination of broom seeds left in the soil.

Cutting the aboveground vegetation of broom and allowing it to dry on site, followed by burning, can effectively control resprouting. Burning is more effective when followed by an herbicide application or subsequent burnings, and then by revegetation with desirable species. It is important to employ a control strategy following a burn, otherwise the broom population in subsequent years may become worse than before.

Grazing can provide control in small areas, if the grazing pressure is high enough to continually suppress growth. Goats and sheep have been shown to feed on resprouting shrubs, including brooms. In horses, however, ingestion of Scotch broom is reported to cause neurologic effects such as excitement and loss of muscle control and balance, as well as digestive and reproductive effects.

Biological Control

In the 1960s, three insects were introduced as biological control agents on brooms—the Scotch broom seed beetle (Bruchidius villosus), the Scotch broom seed weevil (Exapion fuscirostre), and the Scotch broom twig miner moth (Leucoptera spartifoliella). The latter two species are specific to Scotch broom, while the seed beetle also attacks Portuguese broom, Spanish broom, and French broom. Although all three insects are established, none provide significant control.

Recently, a new agent called the Scotch broom gall mite (Aceria genistae) was found in California. Although this small arthropod was not officially released as a biocontrol agent, it has spread across much of Northern California and the Pacific Northwest. Observationally, the mite appears to reduce Scotch broom seed production and at high densities can cause extensive stem dieback and plant mortality. Because brooms are serious problems in many countries, the International Broom Initiative is evaluating other insects and pathogens in their native countries to determine their control potential.

Chemical Control

California residents can use postemergence herbicides containing the active ingredients triclopyr and glyphosate for controlling brooms. These herbicides can be used either alone or as a combination of glyphosate with triclopyr or imazapyr.

In areas near rivers or streams, it is important to use the proper formulation of these herbicides. Ester formulations of triclopyr or imazapyr, for example, are not registered for use near water, and most glyphosate formulations cannot be used near water. Depending on the compound, these herbicides can be applied as foliar sprays, cut-stump treatments, or basal bark applications.

When using herbicides, be sure to prevent them from getting on desirable plants. Because glyphosate is a nonselective compound, it will damage or kill other vegetation. Triclopyr is a broadleaf herbicide that will not injure grasses but will damage or kill other broadleaf plants.

Home gardeners and professional applicators should always wear appropriate protective equipment as stated on the herbicide label.

Foliar Sprays. Herbicides applied to the canopy of broom are often applied when the plants are actively growing from April to July. In mild climates where young broom stems can stay green year-round, late fall and winter applications can also be effective.

Herbicides can be applied as foliar sprays using one of two methods. The first is “spray-to-wet,” where all leaves and stems should glisten following an application. Coverage, however, should not be to the point of runoff. Spray-to-wet applications are made using a backpack or hand sprayer with a flat fan or adjustable spray nozzle. The other foliar method is a low-volume technique called a “drizzle” application, using a spray gun fitted with an orifice disk.

Rather than spraying the entire canopy as in a spray-to-wet treatment, a drizzle application is made to the canopy using an intermittent pattern. It is important to note that the two foliar techniques use the same amount of herbicide active ingredient on a given plant but within different total volumes of water. In a spray-to-wet application, total spray volume can range from 20 to 100 gallons per acre, while the total volume using the drizzle technique will be between 2 and 5 gallons per acre.

The drizzle application is useful for managing plants in areas that are difficult to access. The drizzle nozzle will reach a target plant 15 to 20 feet away, while a flat fan nozzle may only reach plants 2 to 3 feet away. Because of larger spray droplets, the drizzle method also minimizes herbicide drift. The lower volume of water used also reduces sprayer refilling requirements and total weight, potentially reducing applicator fatigue.

For spray-to-wet applications, products containing at least 41% glyphosate as the active ingredient can provide good to excellent control of brooms when applied at 2.5 ounces of product per gallon of water (2% of the total solution). Some products available for use in the home landscape with this concentration of active ingredient are Roundup Pro, FarmWorks Grass & Weed Killer 41% Glyphosate Concentrate, RM43 Total Vegetation Control, Compare-N-Save Grass & Weed Killer Concentrate, and Remuda Full Strength.

Glyphosate products that have a lower concentration of active ingredient, such as Roundup Concentrate (18% active ingredient), will require about 6 ounces of product per gallon of water (4.7% of the total solution) for effective control.

Triclopyr is available in either ester or amine formulations. Triclopyr ester is more effective on brooms, since this formulation is more easily absorbed into the foliage and stems. Products containing a minimum of 61% active ingredient of triclopyr ester can provide good to excellent control when applied at 1 to 1.25 ounces of product per gallon of water (0.75% to 1.5% of the total solution). One such product with this concentration is Brushtox Brush Killer with Triclopyr. Other less concentrated formulations, such as Crossbow, are also available.

Mixing triclopyr ester with commercially available seed oils can offer better penetration. One available product is Hasten-EA modified vegetable oil concentrate. Mix this at 1.25 ounces of product per gallon of herbicide solution (1% of the total solution).

Amine formulations of triclopyr include Bayer BioAdvanced Brush Killer Plus, Ortho GroundClear Poison Ivy & Tough Brush Killer1, and Monterey Brush & Vine Control.

For drizzle applications (low volume, as per product labels), products containing at least 41% glyphosate can provide good to excellent control of brooms when applied at 13 ounces of product per gallon of water (10% of the total solution).

Triclopyr ester can also be applied using the drizzle method. Products containing 61% active ingredient should be applied using 13 ounces of product (10% of the total solution) and 13 ounces of seed oil (10% of the total solution) per gallon of water.

Since drizzle applications use more concentrated herbicide solutions, one gallon of herbicide solution may adequately treat up to one-half acre of densely populated broom.

When air temperatures are higher than 80°F, it is better to use glyphosate or the amine formulation of triclopyr, since triclopyr ester is subject to vaporization.

Cut-Stump Application. Cut-stump treatments can be done throughout the year. Immediately after cutting, apply the herbicide to the cut surface with a paint brush, spray bottle, or plastic squeeze bottle. Delaying application will result in poor control, because the cut surface will quickly dry, preventing movement of the chemical into the plant.

For small stumps, completely cover the cut surface. For large stumps, it is only necessary to wet the outer ring of wood next to and including the bark. For small-stemmed shrubs, cut the stems with loppers or clippers and paint or sponge the herbicide solution onto each cut end.

For triclopyr ester products containing 61% active ingredient, use 1 part product and 4 parts water. For triclopyr products containing 8% amine, such as Ortho Poison Ivy Tough Brush Killer1 use undiluted.

Glyphosate can also be used as a cut-stump application. If using a product containing 18% glyphosate, make a 1:1 solution of the product and water or use undiluted. For products that contain 41% glyphosate, use 1 part product and 3 parts water.

Basal Bark Application. Concentrated formulations of triclopyr ester can be applied to the trunks of broom using a backpack sprayer, spray bottle or wick applicator. Thoroughly cover a 6-inch band around the basal trunk of the shrub. Basal bark applications can be made almost any time of the year, even after leaves have senesced. For triclopyr ester products with 61% active ingredient, the application ratio is 13 ounces of product (10% of the total solution) and 25 ounces of seed oil (20% of the total solution) per gallon of water.

Glyphosate and the amine formulation of triclopyr provide poor control using this technique.

After implementing a control technique, it is important to monitor the area for regrowth. One application of an herbicide does not always completely control brooms. Watch treated areas closely for at least a year and retreat as necessary.

RESOURCES

UC Master Gardeners. (Accessed June 8, 2020).
The PlantRight Program. plantright.org/ (Accessed June 8, 2020).

REFERENCES

Bossard C, Randall J, Hoshovsky MC. 2000. Invasive Plants of California’s Wildlands. Berkeley: University of California Press. (Accessed June 8, 2020).

DiTomaso JM, Healy EA. 2007. Weeds of California and Other Western States. UC ANR Publication 3488. Oakland, CA.

DiTomaso JM, Kyser GB, et al. 2013. Weed Control in Natural Areas in the Western United States. Davis: University of California Weed Research and Information Center. (Accessed June 8, 2020).

Hoshovsky MC. 1986. Element Stewardship Abstract for Spartium junceum (Spanish Broom). (PDF) Arlington: The Nature Conservancy. (Accessed June 8, 2020).

Oneto SR, Kyser GB, DiTomaso JM. 2010. Efficacy of Mechanical and Herbicide Control Methods for Scotch Broom (Cytisus scoparius) and Cost Analysis of Chemical Control Options. Journal of Invasive Plant Science and Management 3:421-428.

Parker IM. 2000. Invasion dynamics of Cytisus scoparius: A matrix model approach. Ecological Applications 10(3):726-743

Parker IM. 2001. Safe site and seed limitation in Cytisus scoparius: Invasibility, Disturbance, and the Role of Cryptogams in a Glacial Outwash Prairie. Biological Invasions 3(4): 323-332.

PUBLICATION INFORMATION

AUTHORS: Scott R. Oneto, UC Cooperative Extension, Joseph M. DiTomaso, Plant Sciences, UC Davis, and Guy B. Kyser, Plant Sciences, UC Davis.

TECHNICAL EDITOR: K Windbiel-Rojas

ANR ASSOCIATE EDITOR: AM Sutherland

EDITOR: B Messenger-Sikes

Produced by University of California Statewide IPM Program

PDF: To display a PDF document, you may need to use a PDF reader.

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2020 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California


Native range map of Cytisus scoparius

Scotch broom was first admired by botanists for its bright yellow blooming and dense growth. Horticulturists happily offered the plant, and others of the Cytisus family, for purchase to their customers for landscaping purposes.

However, in the late 20 th century, awareness rose about how invasive the plant could be. There wasn’t even any point in letting it grow, since the shrub doesn’t make for good fodder. Additionally, it is rated as an extreme fire hazard: a few licks of a candle and the entire shrub might ignite in dry weather.

Many state and national programs today try to eradicate this threat to local biodiversity. In California, a particularly fire-prone state, fire prevention plans even call for pulling the plant out wherever possible.

Map of where Scotch broom, Cytisus scoparius, comes from

Native range: Austria, Belgium, Belarus, Bosnia and Herzegovina, Czech Republic, Croatia, Denmark, France, Germany, Hungary, Ireland, Italy, Lithuania, Kosovo, Moldova, Montenegro, Macedonia, the Netherlands, Norway, Poland, Portugal, Romania, Spain, Serbia, Sweden, Switzerland, Ukraine, United Kingdom

Invasive range: Australia, New Zealand, Canada, United States, Japan, Chile and Argentina, India, Iran, South Africa (the country)

In green, on the map below, you can see where the plant is native to. Even within these areas, however, it is sometimes listed as an invasive weed because it can take over land from less combative species.


Additional information on Scotch broom

Because Scotch broom is so widespread, property owners in King County are not required to control it and we are not generally tracking infestations. We can provide advice on how to control Scotch broom, but there is generally no legal requirement to do so. Many public agencies and conservation organizations are actively working to remove Scotch broom where they have the resources, and may have opportunities for you to volunteer. However,only remove Scotch broom where you have permission to work! For information on useful tools for removing woody plants like Scotch broom, see this post by Northwest Illinois Forestry Association. King County residents can borrow a Weed Wrench or other similar tools from the Noxious Weed Control Program. For more information, contact our office.


Scotch broom is beautiful, but noxious

CORVALLIS, Ore. – Although admired for its yellow blooms, the Scotch broom shrub has become an invasive species throughout the Pacific Northwest, where it competes with native plants and forms dense stands that are difficult to manage and remove.

Scotch broom was introduced from Europe as a garden ornamental by early settlers of the Pacific Coast. Later it was used to prevent erosion and stabilize banks and sand dunes. The woody shrub establishes quickly in disturbed areas, according to Andy Hulting, a weed specialist for the Oregon State University Extension Service.

"Its invasive habit and economic costs have landed Scotch broom on the State Weed Board's list of noxious weeds, along with its relatives French, Portuguese and Spanish brooms and gorse," Hulting said. Scotch broom costs Oregonians an estimated $40 million per year in lost timber revenue and control efforts.

What can you do to control this noxious weed? Prevention is the best method, especially in areas where the ground and other plants have been disturbed by overgrazing or development, Hulting said. Care should be taken not to transport soil that is contaminated with Scotch broom seeds.

"Quickly re-vegetate disturbed sites with fast-growing, competitive native plants to limit Scotch broom spread," he said. "Native trees (such as Douglas-fir or red alder), shrubs (such as woods rose, currants and snowberry) and native grass mixes can help prevent and slow Scotch broom infestations."

OSU Extension recommends that you learn to identify Scotch broom and the other non-native broom species in the Pacific Northwest that have the potential to become weedy. The publication, Scotch Broom (PNW 103), which has color photos, identification information and control measures, is available online.

If you find Scotch broom on your property, Hulting recommends:

  • Dig it up, including the crown.
  • Cut it back to the ground each year before it sets seed.
  • Keep an eye out for seedlings each spring and pull them up, roots and all, while they are small.

Since Scotch broom seed lasts for years in the soil, vigilance is necessary to prevent reinvasion by new seedlings.

Several broad-spectrum herbicides, including glyphosate and imazapyr, can be effective in controlling Scotch broom infestations. Avoid spraying when plants are blooming the flowers can prevent thorough coverage to plant tissues.

"Be careful when using herbicides to minimize drift and injury to non-targeted plants," Hulting warned. If you are unsure about the use of herbicides, contact your county Extension educator.

Remember to wear protective clothing, read the label and follow instructions, and be cautious. You can be liable for injury or damage from herbicide use.

Scientists continue to investigate biological control possibilities for Scotch broom and other noxious weeds. The Oregon Department of Agriculture has released a species of seed weevil whose larvae feed on the developing Scotch broom seedpods. They can destroy up to about 80 percent of the broom seed inside the pods.

You can pop open a mature, brown Scotch broom seedpod to see if seed weevils are working. Look for tiny white larvae. Do not spray plants with seed weevils.


Watch the video: Day 1: 05 - Scotch Broom Gall Mite


Comments:

  1. Fridolf

    Fascinating topic

  2. Bealohydig

    mmm Right.

  3. Gokinos

    Only recently became your reader and immediately subscriber. Thanks for the post.

  4. Garwig

    I congratulate, what necessary words ...

  5. JoJokora

    Wonderful! Thanks!

  6. Maddock

    What words ... super, great thought

  7. Iver

    I think you will allow the mistake. Enter we'll discuss it. Write to me in PM, we will handle it.



Write a message