Greenhouse Operations and Plant Propagation in Zion National Park

In Zion National Park, GBI has been providing assistance with greenhouse operations and plant propagation. This work has involved seed cleaning, seed stratification, pest control, and potting up, all in the interest of producing populations of key grasses, forbs, and shrubs that can be used for post-construction planting along the Kolob Canyon Road. This past winter, the greenhouse team’s efforts were focused on sowing seeds and taking cuttings from mature plants.

An Echinocereus triglochidiatus (claretcup cactus) blooming in our greenhouse.

Successful seed sowing attempts to mimic the natural conditions in which these seeds would thrive. For example, if a species seed normally undergoes an embryonic dormancy phase, then it might need to be exposed to winter conditions in order to germinate, requiring the team to place it in a cold, moist medium. Other questions the team might ask of these species include: Would the seed normally be physically altered in some way as it moves through an animal’s digestive tract? Would it be exposed to regular freeze/thaw cycles? Or to microbial activities?  Additionally, greater care must be taken with seeds from endangered species. The photo at the top of the page shows cones used for seed sowing.

The cutting process involves removing a portion of a mature plant, then creating conditions that encourage the cutting to form roots. For this, the team had to take care to remove cuttings of the proper size and in the best season. As with seed sowing, different species require different approaches, with some taking root more readily than others. Prickly pear cactus, for example, can be lopped off at the node, stored for several weeks, then placed in appropriate soil with considerable success. Grape vines, on the other hand, require more diligence on the part of the greenhouse team.

And that diligence has paid off, with the team racking up some impressive numbers. Since January it has sown 5974 seeds and potted 187 cuttings. And all of this is in addition to general maintenance and additional duties, including pest control and database management.

A beautiful Astragalus zionis (Zion astragalus) blooming in our increase field.

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