Propagation of Two Utah Native Plants: Ceanothus velutinus and Cercocarpus montanus

Among various water conservative approaches, the use of native plants in landscape, such as Ceanothus velutinus (snowbrush ceanothus) and Cercocarpus montanus (alder-leaf mountain mahogany), is attractive. Efficient propagation methods are required to allow these native species to use in water-efficient landscaping. Sexual (seed) and asexual/vegetative (cuttings and micropropagation) propagation methods were evaluated. Seeds of both C. velutinus and C. montanus were scarified and/or stratified and treated with gibberellic acid (GA3) to break dormancy. The results showed hot water scarification and 2-3 months of stratification effectively broke the dormancy of C. velutinus seeds, and stratification for 2-3 months was needed for C. montanus seeds. Furthermore, GA3 also helped to increase germination of both species. Terminal cuttings of C. velutinus were collected from May to Sept. 2019 and June to Aug. 2020 from the Tony Grove Lake area, Utah. Terminal and stem cuttings were also collected in Aug. 2019 from the same area. Likewise, different rooting hormones were tested using cuttings collected from greenhouse-grown seedlings. Ceanothus velutinus cuttings collected in July tended to have a better rooting percentage than those collected at other times of the year. Hormodin 2 [3,000 mg·L-1 indole-3-butyric acid (IBA)] tended to be the better rooting hormone. Terminal cuttings were good compared with stem cuttings but were not significantly different in terms of rooting percentage. Terminal cuttings of C. montanus ‘Coy’ were collected in mid-July and different rooting hormones were tested. Hormodin 2 tended to be the better rooting hormone. A separate experiment was also conducted using terminal and stem cuttings. Stem cuttings tended to be better for C. montanus. In addition, on 11 May, 2020, hardwood stem cuttings were collected and wounding study was performed. Wounding promoted adventitious root formation of C. montanus. For micropropagation, Murashige and Skoog (MS) and Gamborg’s B-5 (B5) medium supplemented with 1 mg·L-1 benzylaminopurine (BA) were better than other medium for establishment of C. velutinus. In addition, ex vitro rooting study was successful for rooting microshoots of C. velutinus. For C. montanus, MS + 1 mg·L-1 BA tended to be better medium for multiplication stage