Germination rates of Bouteloua gracilis (Blue Grama) under different concentrations of magnesium chloride

Background/Question/Methods

Magnesium chloride (MgCl₂) is a type of salt commonly used for dust road suppression and road deicer, as seen in Colorado.  Blue Grama, Bouteloua gracilis, is a native grass to Colorado known for its erosion control, cattle forage, and habitat restoration.  The purpose of this study was to determine how different concentrations of MgCl₂ effect the germination rate of Blue Grama.  Growth trays were treated with 500 ml of D.I. H₂O with MgCl₂ contaminates along with 1000 ml of tap water.  Seeds (n=100) were sown in each tray and total number of germinates was counted every day for a week following sowing.  Within these three water conditions there were 4 different growth trays with different concentrations, of MgCl₂ contamination: 0.00M (control), 0.01M, 0.05M, and 0.10M.  The trays were given a two week degradation period before the seeds were sown.  Every seven days after sowing, the trays were rehydrated with 500 ml of tap water

Results/Conclusions

                Means for each week were compared between MgCl₂ treatments and the control using a T-test to determine P-values.  Germination rate of Blue Gama varied per tray.  Trays with 0.01M, 0.05M, and 0.10M yielded P-values signifying difference of control of 0.164, 0.042, and 0.038 respectively.  Therefore the trays contaminated with 0.05M and 0.10M of MgCl₂ had significantly lower germination rate then the control groups.  Shoots of the 0.10M tray were also chlorotic.  The results suggest that water laced with greater concentrations of MgCl₂ will prevent and hinder Blue Gama (a Colorado native grass) to germinate.  The results question the use of MgCl₂ as a deicer with in the natural habitats of the grass in order to allow the native species to perform ecosystem services.