Table 1 shows identifying features of these four broom species.Īll four broom species produce dark colored pods in mid- to late summer that contain shiny greenish-brown seeds. Scotch, Portuguese, and Spanish brooms are deciduous while French broom is an evergreen. 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. Spanish broom produces simple leaves, while the other three species have mostly trifoliate leaves. Leaf characteristics also identify the 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. Stem shape can be used to distinguish between broom species. Bridal veil broom ( Retama monosperma) is a white-flowered broom that has become invasive in parts of Southern California. In some areas, Scotch broom flowers can be multicolored, with red or purple spots or petals. The flowers of French broom are substantially smaller than those of the other three common species. Scotch and Portuguese brooms produce their flowers in the leaf axils, while French and Spanish brooms have flowers at the branch tips. They generally produce bright yellow, pea-shaped flowers from April to June. IDENTIFICATION AND BIOLOGYīrooms are upright shrubs that grow 3 to 10 feet tall. Contact your county UC Master Gardener office or visit for a list of recommendations (See RESOURCES). Several alternate plant species have similar attributes but are not invasive. The safest approach is to avoid planting any broom species. 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. Residents should avoid planting them as many of these have similar invasive characteristics. 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).Īlthough many retailers have stopped selling the species mentioned above, some nurseries still sell these and other brooms, including many hybrids. 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. Their dense stems make regeneration of most other plant species difficult or impossible, and they create a dangerous fire hazard. These highly competitive shrubs grow rapidly and form dense stands that both people and wildlife find impenetrable. As a result, five broom species have become naturalized in California and are classified as invasive weeds by many federal, state, and local jurisdictions. Initially introduced as ornamentals, they were later promoted by federal and state agencies for erosion control along roadsides and in mined areas. Brooms can be found growing along roadsides, forestlands, coastlines, riparian areas, brushlands, and disturbed areas. Brooms are a group of shrubs that were introduced into North America from Europe and North Africa in the mid-1800s.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |