Tree-of heaven is an invasive weed. A tree of heaven it is not! It was initially valued as an urban street tree and was widely planted in the United States particularly around the Baltimore and Washington D.C. area.
Tree-of heaven can reach heights of 80 feet and grow to 3 feet in diameter. The tree has smooth grey bark, stout, blunt, chestnut brown twigs, and a long compound leaf ranging in length from 1-4 feet with as many as 30 leaflets. The leaflets are smooth-edged except for 1-3 teeth near the base. Clusters of twisted papery seeds, called samaras, often hang on the trees over winter. The wood is soft, weak, course grained, and creamy white to light brown in color. All parts of the tree, especially the flowers, have a strong, offensive odor. Tree-of-heaven is often found growing in clusters as new shoots grow from the roots.
This species is easily confused with walnut trees. The foul odor produced by the crushed foliage and the scraped bark is also unique to tree-of-heaven.
Established trees constantly spread by sending up root suckers that may emerge as far as 50 feet from the parent tree allowing them to rapidly dominate sites.
Using only mechanical methods for controlling tree-of-heaven may be counter-productive since the tree responds to cutting and girdling by producing large numbers of stump sprouts and root suckers. Hand pulling of young seedlings may be effective when the soil is moist and the entire root system is removed. However, very small pieces of root are capable of generating new shoots.
The most effective approach for controlling tree-of-heaven includes the use of herbicides applied to foliage, stems, or cut surfaces. Persistence is the key to success.
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Almost every plant has one or more aphid species that occasionally feed on it. Although aphids can curl leaves and produce stick honeydew, they rarely kill plants. When aphid numbers are high, natural enemies frequently feed on them. When pesticides are necessary, use less toxic products.
Aphids are common in your garden because:
Aphids like lush new growth. Don't over fertilize.
Aphids build up on flowering plums, roses, tulip trees, crape myrtles, apples and many vegetables. Expect aphids when you grow these plants.
Ants protect aphids from their natural enemies. Keep ants off plants.
To reduce aphids:
Prune out infested leaves and stems.
Knock aphids off plants by shaking the plant or spraying a strong stream of water.
Protect seedlings with covers.
Wait for hot weather; most aphids are heat-intolerant.
Protect aphids' natural enemies:
Lady bugs (larvae and adults), lacewings, syrphid fly larvae, soldier beetles and parasitic mini-wasps.
Beneficial insects will come into your garden naturally when aphids are abundant. Protect these good bugs by avoiding the use of insecticides that can be toxic to a broad variety of insects.
If insecticides seem necessary, use the safest products:
Use nonchemical pest control methods first.
Insecticidal oils and soaps are the safest products. When properly used, these will solve most insect problems.
Oils and soaps work by smothering aphids, so apply thoroughly.
Soaps and oils are best for vegetables and roses. For larger trees such as crepe myrtle use a narrow range horticultural oil.
Systemic insecticides can kill bees and beneficial insects.
Rose plants get a lot of aphids in the spring. My tip is to squish them. I get great satisfaction squeezing the aphids between my fingers.
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Such a silly name for a bad, bad weed.
This weed seemed to appear overnight in 2010. It is invasive!
Catchweed bedstraw is a summer annual broadleaf plant that is starting to show in your gardens now! Its bristles attach to people's clothing and the hair of animals, aiding in its dispersal. If you have this plant, get rid of it now. It is very distinctive with a square stem and sticky feeling.
Mature plant
Stems are square and have tiny down-curved prickles. Mature plants reach up to 3 feet long. Leaves whorl around the stem in groups of six to eight. Individual leaves have a rounded tip, and tiny curved prickles on the leaf edges and midveins that, under a lens, are seen pointing toward the leaf base giving the leaves a sticky touch.
Flowers
Flowers bloom from March through July. Two to nine tiny, greenish to white or yellowish, four-petaled flowers cluster on long stalks from the main stem above the leaf whorls.
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Gophers are small burrowing rodents that feed on roots of many plants. A single gopher can ruin a garden in a short time and gopher gnawing can damage irrigation lines and sprinkler systems. Early detection is critical to prevent damage. Combine the use of traps and underground fencing to manage problems. Toxic baits are available but can pose threats to wildlife, pets and children, especially in backyard situations.
Keep your eye out for gopher mounds.
Gophers spend almost all their time underground in their burrow.
Look for mounds of loose dirt that are half circles or crescent shaped.
Fresh mounds are the sign of an active gopher. A single gopher can create several a day.
In contract to gopher mounds, mole mounds are circular with a plug in the middle and ground squirrel holes are unplugged without a mound.
Protect plants with underground fencing.
Lay hardware cloth or ¾ inch mesh wire under raised beds before planting.
Wire baskets can also help.
Use traps to reduce the gopher population.
Gopher traps are placed underground inside the burrow, so you must use a probe to locate the burrow.
Be sure to place traps in active burrows.
Two common types of traps are pincer and box traps.
Cover the hole so light does not get in.
Check traps often and reset as necessary.
Keep trapping until no new mounds are formed.
Gopher traps do not require food baits.
Avoid products and methods that are not proven.
Owl boxes are unlikely to reduce gopher numbers.
No repellents currently sold work.
Plants such as gopher purge, castor bean and garlic have not been shown to repel gophers.
Frightening devices have not shown to be effective.
Fumigation with smoke or gas cartridges is not effective because gophers can seal off their burrows rapidly.
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Both sprinkler and drip irrigation systems should be checked regularly for broken components for leaks that may otherwise go undetected. Examples are clogged nozzles, worn nozzles, tilted sprinkler heads and heads in the same zone with varying output rates. Also look for signs of leaky valves in your control box, such as water continually oozing around sprinkler heads. Correcting these problems often reduces water waste by 20%.
Learn to recognize plant drought symptoms
Under drought foliage may lose its luster, shrivel and droop. Turf will hold a footprint. Overtime plant growth is reduced. Stems and twigs toward the outer parts of the plant begin to defoliate and may eventually die. Finally, the entire plant may die if water is not provided. Ideally, irrigation should be applied before plants show pronounced systems.
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