Rio Verde LabLab G. R. Smith, F. M. Rouquette, Jr., and I. J. Pemberton, Texas Agricultural Experiment Station, Texas A&M University Agricultural Research and Extension Center, Overton, TX 75684.

Lablab is a vining, annual tropical legume with high nutritive value as a forage or browse for ruminant animals.  The qualities of this tropical forage include: drought tolerance, high palatability, high nutritive value, excellent forage yields and adaptation to diverse environmental conditions. 

‘Rio Verde’ lablab was developed through selection for tolerance to defoliation, forage production potential and Texas seed production. Rio Verde was developed at the Texas A&M University Agricultural Research and Extension Center at Overton, Texas and released by the Texas Agricultural Experiment Station (TAES) in 2006. Rio Verde is the first lablab cultivar developed in the US and also has the value-added trait of Texas seed production.  Rio Verde lablab should be planted in May and will start flowering in late August.  Forage production of Rio Verde will continue until frost and yields will range from 1.5 to 2.5 T/acre of dry forage.  Nutritive value of Rio Verde forage is high with crude protein at 25% or higher in the leaves and 12% in the stems.

Rio Verde is adapted to sandy, sandy loam, clay loam and clay upland soils of the US southern region, including the following regions of Texas: Pineywoods; Gulf Prairies and Marshes; Post Oak Savannah; Blackland Prairies; Cross Timbers and Prairies and South Texas Plains.  In the lower rainfall areas of the Cross Timbers and the South Texas Plains, irrigation may be required for establishment.  Lablab does well on a wide variety of well-drained soils but does not tolerate waterlogging.  This cultivar will establish, survive and be productive with 10 inches of rain during June – Oct. in northeast Texas. 

For more information contact Dr. Ray Smith at 903-834-6191 or see the TAES Overton website (http://overton.tamu.edu/rioverde/index.htm). Rio Verde is available from Pogue Agri Partners, Kenedy TX (800-582-4769).

Management Guide for Rio Verde Lablab

1. Choose well-drained sites with sandy, sandy loam or clay loam soils. 
    
2. Fertilize and lime according to soil test.  Lablab will tolerate soil pH levels ranging from 5 to 7.5.  Some iron deficiency chlorosis will be noted in soils with pH > 7.5.  
   Inoculate seed using cowpea inoculants. 
    
3. Plant 15 to 20 lbs of Rio Verde seed per acre on prepared seedbed. Use a drill to place seed about 1 to 1.5 inches deep. 
    
4. An alternative planting method is to broadcast seed on disked seedbed and follow with a light disking to cover.  Use care to not cover the seed more than about 1.5 inches deep.Rio Verde can be planted in Texas from May through July, according to soil moisture.  Early fall (Sept.) plantings may also be used if soil moisture is adequate. 
    
5. Rio Verde will start flowering in late August but will be productive until frost.  Research is in progress on the reseeding potential of this new forage legume. 

Utilization Recommendations

• Wildlife Browse – Excessive defoliation by deer post-germination may require electric fencing, etc, to protect the small seedlings.  This is dependant on size of area planted and density (population) of deer. With the excellent nutritive value and palatability of lablab, this forage may be used as a direct browse crop or as hay for supplementation or as an attractant.
   
• Livestock Grazing – Lablab tolerates moderate defoliation and may be most sustainable when either rotationally stocked or used as a creep-grazing area for suckling calves. Frequent and severe defoliation by the grazing animal may result in loss of plants and/or stand. When using a rotational stocking system, it’s recommended that grazing be terminated when an approximate 4-inch stubble height is reached, and that grazing may resume when lablab reaches a 12 to 15-inch height. The number of grazing cycles is moisture dependent.
   
• Hay Harvest – Rio Verde lablab should make sufficient growth during the summer months to provide 2 to 3 hay harvests. It is suggested that cutting height be maintained at 4-inches or higher to allow for adequate re-growth. Due to stem size, a cutter-conditioner would be preferred; however satisfactory hay can be made with cutting, tedding, windrowing, and baling. Hay should be stored under protective cover from rainfall. Some leaf shattering will occur during hay feeding; thus, losses would be minimized by feeding in a bunk or with restricted access by livestock.
   
• Green Manure Crop – Lablab is an excellent source of green manure crop, and for maximum N-fixation, incorporates lablab via disking at end of growing season (Sept-Oct). Lablab may be disked into the soil with or without shredding. More than one disking may be required to adequately incorporate the above-ground forage growth. The N-fixed via incorporation will often be an adequate N source for a following small grain crop. Alternative management could include a hay harvest in mid-summer prior to disking as a green manure crop; however, total N-fixation will be reduced.