Heteranthera (dubia)

John M. Englert USDA NRCS - Norman A. Berg National Plant Materials Center Bldg. 509, BARC - East, E. Beaver Dam Road Beltsville, Maryland 20705 (301) 504-8175 (301) 504-8741 (fax) john.englert@wdc.usda.gov http://plant-materials.nrcs.usda.gov/mdpmc/

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Family Scientific Name:	Ponteridaceae
Family Common Name:	Pickerelweed Family
Scientific Name:	Heteranthera dubia (Jacq.) MacM.
Common Name:	Water stargrass
Species Code:	HETDUB
Ecotype:	Gunpowder River near Aberdeen Proving Ground, MD
General Distribution:	Water stargrass is a freshwater perennial submerged aquatic that grows throughout most of the United States in streams and quiet bodies of water, such as lakes and ponds. It will tolerate up to 5 parts per thousand salinity (Chesapeake Bay Foundation, 2001). The species tends to grow in clay and mud soils, but has also been documented growing in gravelly sediment (Hurley, 1992). Water stargrass has attractive yellow flowers that typically appear on wild plants during the summer months; on our greenhouse grown plants (under supplemental lighting), flowers are produced year-round.
Propagation Goal:	plants
Propagation Method:	vegetative
ProductType:	Container (plug)
Time To Grow:	0
Target Specifications:	Plants are grown in containers, but are used as bareroot transplants or with little soil clinging to roots and stolons. Plants are considered to be transplant ready when roots have spread throughout the pot and new shoots are developing. We do not have a target plant height, although many plants, when ready for transplanting, have stems longer than 40 cm.
Propagule Collection:	We take cuttings from stock plants maintained in our greenhouse because of state restrictions on harvesting material in the wild; material for stock plants was originally collected as wrack (floating plant parts) in the field prior to implementation of a permitting process. Cuttings approximately 15 cm long are collected from any part of the stem (main shoots, sideshoots, flowering stems, stem tips, and midsections). Cuttings can be taken from greenhouse stock plants any time of year.
Propagule Processing:	As cuttings are taken, they are dropped into a holding bucket of water; generally, they are stuck in medium right away, but if this is not possible, cuttings may be left in room temperature tap water for a day or two.
Growing Area Preparation/ Annual Practices for Perennial Crops:	We grow cuttings (as well as stock plants) in a 5130 L freshwater tank in a greenhouse. Water is continuously flushed through a 2 sponge filter and is maintained in the tank at the depth of 45 cm (which is the maximum depth available in the tank) with the addition of tap water as needed. Water temperature fluctuates with the surrounding air temperature in the greenhouse between 20 and 25C. Daylength is kept fairly constant, around 14 h. Natural daylength is augmented during the winter months by 5 h of light supplied by four 1000 watt sodium lamps suspended along the center tank, 2.6 m apart and 1.8 m above the tank. The greenhouse is covered with a whitewash solution that provides 30% sunlight shading from mid-April to October. Growing media for cuttings used is inexpensive topsoil (enough to fill 5 cm wide x 10 cm deep pots to within 1 cm of top, packed) mixed with 1.2 g of Nutricote slow release fertilizer (18:6:8, 180 day release rate at 25 C). This soil-fertilizer mix is covered with a minimum of 6 mm of washed play sand to reduce algae formation on the growing surface. Filamentous algae tends to be a problem in the tank, and is removed with a hand net when the sponge filter does not adequately capture it. Barley straw bales were unsuccessful in controlling algae, although bacterial treatments were partially successful in breaking down algae.
Establishment Phase:	Cuttings do not require rooting hormone, and are stuck 2 per container, either vertically with the bottom inch of the cutting anchored into the soil mix, or laid in a coil completely covered by the sand layer. When started in February, cuttings 15 cm long generate new roots in 1 week.
Length of Establishment Phase:	1 week
Active Growth Phase:	Cuttings continue to generate additional root mass and shoots and rhizomes after establishment.
Length of Active Growth Phase:	5 weeks
Harvesting, Storage and Shipping:	Plants generated from cuttings are ready for outplanting on revegetation sites in 5 weeks when started in February. Plants may be placed in coolers of water or covered with wet newspaper for local transport (either same day or overnight).
Other Comments:	The U.S Army Corps of Engineers has included a growing protocol for water stargrass from tip cuttings in its publication Propagation and Establishment of Aquatic Plants: A Handbook for Ecosystem Restoration Projects (see References for complete citation). Other sources (Hurley, 1992) report seed production on wild plants, however, we were not able to find any seeds forming after flowering occurred on our stock plants. Wildlife Value: Water stargrass is only slightly used as food by some species of ducks. The Maryland Department of Natural Resources maintains a Web site listing of sources of laboratory and greenhouse produced SAV, for those wishing to obtain plants for restoration projects (see References).
References:	Chesapeake Bay Foundation. 2001. Guide to Underwater Grasses. Chesapeake Bay Foundation. Annapolis, MD. URL: http://www.cbf.org (accessed 3 February 2003). Godfrey, Robert K. and Jean W. Wooten. 1979. Aquatic and Wetland Plants of Southeastern United States: Monocotyledons. University of Georgia Press. Athens, GA. Hurley, Linda M. 1992. Field Guide to the Submerged Aquatic Vegetation of Chesapeake Bay. US Fish and Wildlife Service. Annapolis, MD. Maryland Department of Natural Resources Submerged Aquatic Restoration Research Center Plant Sources. Maryland Department of Natural Resources. Annapolis, MD. URL: http://mddnr.chesapeakebay.net/savrrc/plant_source_information.html (accessed 3 February 2003). Smart, R. Michael and Gary O. Dick. 1999. Propagation and Establishment of Aquatic Plants: A Handbook for Ecosystem Restoration Projects. Technical Report A-99-4. Aquatic Plant Control Research Program. U.S. Army Corps of Engineers Waterways Experiment Station. Vicksburg, MS.

Citation:

Kujawski, Jennifer L.; Thompson, Randall. 2006. Propagation protocol for production of Container (plug) Heteranthera dubia (Jacq.) MacM. plants USDA NRCS - Norman A. Berg National Plant Materials Center Beltsville, Maryland. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/07/23). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.