Invasive Plants – GrowIt BuildIT

If you are reading this, you probably have just encountered a tall yellow-orange flowering plant with some of the softest leaves you've ever touched! In fact you also may notice it all over the area you are standing in, as it is quite prolific! Congratulations, you've discovered Velvetleaf, one of the most prolific failed cash crops from Asia that American farmers tried to grow. And all because we needed some rope! I'm going to tell you all about this invader from Asia. The history, the good, the bad, the uses, and the ugly..... In this article: What is VelvetleafIdentification / Characteristics of VelvetleafWhy is Velvetleaf in North America?What is Velvetleaf good for?Velvetleaf is invasiveHow to Control VelvetleafGrowing Conditions/CultivationWhat Wildlife, Pests, and Diseases effect Velvetleaf What is Velvetleaf Velvetleaf is an annual flower native to China, Central and Southeast Asia. Scientifically known as Albutilon theophrasti, this invasive weed can grow 7-8' tall in optimum conditions and crowd out native plants and row crops alike. A prolific spreader, there are few habitats that it cannot grow and each plant can produce up to 8000 to 17000 seeds. [1] So, as an annual each Velvetleaf plant will die in freezing Winter temperatures. But the huge quantity of seed produced make this an incredibly invasive species. Native Range of Velvetleaf The native range of Velvetleaf is Southeast Asia, China, and India. Unfortunately it has colonized the Continental United States and all Southern Provinces of Canada. [2] [3] It has invaded the entire continent. Sources [2] [4] [5] Click to enlarge Velvetleaf is found in cultivated farm fields, vacant lots, gardens, powerline cuts - just about anywhere with full sun! It is truly a prolific invasive plant! Even if you think you've eliminated Velvetleaf, it often occurs, or resurges when soil is disturbed. As disturbing soil often brings the seed closer to the surface where it is more likely to germinate. [1] The thing is, Velvetleaf seed can stay dormant deep in the soil for many years. Yet somehow, a seed knows when it approaches the top inch or two of soil, and voila - you have a new Velvetleaf plant the following Spring. Velvetleaf Reference Table FamilyMalvaceae JussScientific Name, Botanical NameAlbutilon theophrastiCommon Name(s)Velvet Leaf, Velvetleaf, China Jute, China Mallow, Indian Velvet LeafNative Range, USDA ZoneAsia, ChinaBloom TimeSummer - Early FallBloom Duration, Color8 weeks, orange to yellowHeight2'-7' (60 - 210 cm)Light RequirementsFull sunSoil TypesSand to clay loamMoistureAverage moistureFauna Associations Bees, butterflies.Sources [1] [2] [3] Identification and Characteristics of Velvetleaf It is pretty easy to identify Velvet Leaf even before it blooms. The large size and large leaves with long stems make it stand out amongst other vegetation. And the yellow flowers and seed capsules are quite identifiable. Furthermore you can just touch the ever so soft leaves and feel their texture like velvet. Stalk On average Velvetleaf grows 3' tall but can reach 6-7' in optimum conditions. The stems are hairless and round, and a light green color. [1] Leaf The leaves of Velvetleaf plant are alternate on the stalk, obicular-cordate i n shape, up to 8" wide and long with long petioles (3-4") . They are dentate or serrated on the margins, and prominent veins. Large leaf on a long stem Flower On the upper leaves single flowers occur that are roughly 1/2"-1" diameter, 5 petals and orange or yellow in color. Flowers are attached to the plant with 1" long peduncles (stems). There are 5 green sepals behind and in-between the petals. Flower of Velvet Leaf with a pollinator The blooming period last from July until Frost. An individual flower is usually pollinated the day it opens, and then the seed fruit forms (and matures) in about 3 weeks. Each seedpod will have 5-45 seeds that are reniform or cordate in shape. Each plant can make up to 200 capsules, which results in a single plant being (theoretically) capable of 17000 seeds! [1] [3] Seed fruit (capsule) of Velvetleaf Root The root system of Velvetleaf is a short tap-root. How Velvetleaf arrived in North America In early American colonial times many goods had to be imported such as fiber cloth and rope. In order to obtain local sources for such material Velvetleaf was imported and attempted to grow as early as the 1600's, as it was reported as being widespread in Virginia and Pennsylvania by 1700. None of these ventures were successful, but people kept trying for another 100-200 years! [3] Reports from the United States Senate from the early 1800's tasked various agencies with identifying and securing supply of cordage so that our Navy may be equipped without relying on foreign sources of rope. [6] All of this created and economic opportunity for enterprising farmers and businessman to manufacture rope using locally grown plants to be used by the US Navy as well as all other shipping. Unfortunately this didn't pan out well due to inefficient machinery that was designed for different plants. Who would've thought rope was a national security issue? Hemp from Russia was a popular import for rope-making due to it's strength. But hemp was also expensive to import, and expensive to cultivate and turn into rope. Reports from the Illinois State Fair in the 1870's state that the cordage from Velvetleaf "was of good quality" and that it could be produced for roughly 1/3 the cost of hemp per acre. This led many farmers to take the plunge and plant it, giving it a new foothold. Those same reports also discussed the weediness of Velvetleaf in cornfields. Unfortunately, from the reports in the late 1800's it appears that Velvetleaf was never an economic success due to standard machinery not being up to task for turning Velvetleaf into rope. And therefore Hemp remained the primary rope making crop for North America, but not before an invasive plant was unleashed throughout the United States and Canada. What Velvetleaf is good for Fiber/rope/cloth Although it is one weedy weed, Velvetleaf does have some benefits. It has been grown in China as far back as 2000bc for use in cordage, rope, fishing nets, and cloth. [1] Food The seeds of Velvetleaf have a high concentration of lipids and can be used as food, as they roughly 20% protein on a dry weigh basis. [1] Seeds are eaten in China when immature. And, the Wild Food Trailguide by Alan Hall does state that all members of the Mallow family are edible. Although some preparation may be required to use as a pot herb (two boils), but the flavor is poor.[12] Toilet Paper Look, sometimes if you go out into nature.....nature may call. And if it does, Velvetleaf makes the absolute finest natural toilet paper a person can find. The Charmin bears got nothing on Velvetleaf! Why Velvetleaf is bad When it comes to vegetative competition, Velvetleaf has a lot of advantages over many plants. From a pure vegetative perspective, it grows fast, can grow fast in partial shade (from surrounding plants), and has a taproot that is great for sucking up nutrients and water. Harms native plants and crops Velvetleaf takes nutrients and sunlight that would otherwise be available to native plants or rowcrops, just like any other weed - it just does it better and more efficient. One study found that in Velvetleaf infested cornfields the yield dropped 70%! That is serious production lost due to an invasive weed stealing nutrients, water and food. [1] Velvetleaf is invasive! I've told you how many seeds a single plant can produce (8,000-17,000), now I'm going to tell you how fast those seeds germinate. A couple studies found that roughly 50% of the seeds germinated within 2.5 years in Mississippi, while 70% germinated within 3 years (Illinois). Other studies found up to 400 seedlings per square meter in a field! So, you can obviously see just how prolific this plant is! [1] [7] It is an extremely competitive plant in crop fields and disturbed areas. It is able to efficiently make sugar from photosynthesis even in partially shaded canopies from surrounding vegetation, so that it may eventually grow taller then the surrounding more established plants. Further aiding the spread of Velvetleaf is a secondary dormancy mechanism within the seed embryo. In addition to a hard outer shell, the embryo has a dormancy trait in that it will not immediately germinate once the outer shell has been broken. No - it will germinate randomly over time, which will help the many seeds increase their chance of survival (at least one of them), as it will be growing in different climate conditions over time. [10] Lots of seed A single Velvetleaf plant can make up to 16,000 seeds in a year. That is a lot, and a lot of future plants to deal with. Studies were done on six cornfields in Nebraska in the early 80's and estimated that each field had upwards of 51 million seeds per hectare. [3] Disclaimer - I only shook out a few seeds to make sure my infestation didn't grow! Tenacious Seeds The seed of Velvetleaf has a particularly hard coat making it resistant to decomposition from digestion. This has been observed numerous times in scientific surveys and studies. [8] [9] Long lived seed The seed of Velvetleaf has been reported to be able to stay viable in the soil for up to 50 years! [1] Velvetleaf seed viability & longevity Just how does the seed of Velvetleaf stay viable for up to 50 years? It is able to do this for several reasons: It has a hard seed coat that is dense. Tannin-like compounds within the seed coat inhibit external microorganisms from destroying the seed. There is nonpathogenic bacteria within the seed. When initially mature, the seeds have a certain 'hardness' that resists water. But after dry storage for a year, the hardness softens and the seed becomes permeable to water. It is likely a combination of this phenomenon and freeze thaw cycles in the soil that lead to the high germination rates observed in the field. To further complicate the seed of this plant, it has been observed that the seed does not germinate immediately after breaking through the seed coat. But in fact, the germination is 'sporadic', which is a form of embryo dormancy that allows for seeds to germinate under different conditions, raising the probability of survival for the plant. [1] [10] How Velvetleaf seed germinates Should one *want* to grow Velvetleaf from seed, you would need to scarify the seed in some manner. Research has shown that soaking in hot tap water overnight is effective at breaking primary seed dormancy, as well as utilizing mechanical scarification via sandpaper. One would then need to plant seeds roughly 5-10 mm deep (1/4"-1/2") in moist potting medium in temperatures that were roughly 70F. [1] How to Control Velvetleaf Residential As Velvetleaf is an annual, it will die out every Winter. So, it is possible to just hand pull specimens when the soil is moist if the infection is small. The plant is large, and the taproot isn't very deep - so pull them. Just make sure the plant winds up in the firepit or the trash so the seed doesn't spread. If the infestation is widespread, say a vacant lot that is overrun, then a herbicide containing 2-4D would be the best way to get it under control. But - in hot sun the leaves can wilt naturally, and herbicide is less effective. So, spray the plants in the mornings when they are young for the most efficient kill. But make sure you follow the label instructions. Agriculture For agricultural situations, post emergent herbicide may be necessary to get Velvetleaf under control. Contact your local extension office for the best methods. However, if Velvetleaf is in the general region, but not present at your fields - then prevention is the best medicine. A thorough power washing of equipment after working in Velvetleaf infested areas is the most economical way to combat this nasty invasive plant. Growing conditions for Velvetleaf Sunlight Requirements Velvetleaf prefers full sun, which is six hours of direct sunlight per day. But it will tolerate partial shade (4-6 hours of sun per day). I have personally found flowers in both conditions. The specimens in partial shade were shorter stature, as one would expect. Soil Requirements For soil, as you would expect from an 'invasive' plant, Velvetleaf is not too particular. It will grow in loam, clay loam, and sandy loam. [1] I have even found several specimens growing on a beach in full sand. For specimens I've located in sandy soil, they were only 2-3' tall, which is much smaller than the 6-7' tall that the plant can reach in more fertile conditions. Moisture Requirements Velvetleaf prefers medium moist conditions for moisture. Wildlife, Pests, and Diseases associated with Velvetleaf Pollinators Velvetleaf is primarily pollinated by bees. Numerous species of bees visit the flowers for nectar and pollen such as bumblebees, leaf-cutters, halictid bees. Butterflies are also reported to visit the flowers, although I've never seen one (but I don't let the plant live, either). Other insects There are many different other species of insect that feed on the foliage or seeds. Plenty of native beetles eat the immature and mature seeds such as the Pennsylvania Ground Beetle, and other species of weevil. There are also some leaf-miners that will feed on the leaves. Deer and Rabbits The fuzzy foliage is generally not bothered by herbivores. Velvetleaf Toxicity I cannot locate any references to Velvetleaf being toxic to pets. [11] When researching this I did come across other websites claiming velvetleaf is toxic to dogs and cats, but they were in regards to a houseplant commonly known as Heartleaf Philodendron, (Philodendron scandens), not Abutilon theophrasti (the subject of this article). So, it appears that this is another case where the common names of plants get confusing. Always check the scientific names of plants when researching toxicity! Learn how to control more invasive plants here