restricted access Propagating native Salicaceae for afforestation and restoration in New York City’s five boroughs

Identifying superior Salicaceae genotypes for afforestation and restoration activities in urban areas can greatly increase the provision of ecosystem services for long-term ecological sustainability. To address this opportunity, we collected native Populus L. (Salicaceae) and Salix L. (Salicaceae) scions from 3 sites on Staten Island, New York, and conducted a propagation study followed by greenhouse and nursery scale-up activities. Our objectives were to: 1) identify hormone treatments that enhanced root initiation and early growth of the native genotypes; 2) incorporate Salicaceae propagation methodology into phyto-recurrent selection; and 3) establish a population of genotypes that can be used for afforestation and restoration efforts throughout New York City. For Objective 1, we tested the response of 112 native genotypes and 11 common clones to 3 root hormone treatments (36-h water soak plus 12-h soak in 1% IBA + 0.5% NAA; 48-h water soak plus powder dip in 0.3% IBA; 48-h water soak plus 5-s dip soak in 20% IBA) and a water soak control. After 75 d of growth, the control treatment was more effective than the 0.3% IBA powder dip and as effective as the other treatments. Given broad clonal variation, there is a high probability of selecting genotypes for both afforestation and restoration. Although Salix exhibited greater relative propagation success than Populus, both genera should be used to increase overall genetic diversity. From a practical standpoint, scale-up activities led to establishment of a nursery population that will be used for ongoing afforestation and restoration activities in New York City.

Zalesny RS Jr, Hallett RA, Falxa-Raymond N, Wiese AH, Birr BA. 2014. Propagating native Salicaceae for afforestation and restoration in New York City’s five boroughs. Native Plants Journal 15(1):29–41.