Plant Propagation

Course Schedule - Week 12

Considering that you've already propagated a number of (geophytic) plants by dividing (for the most part) their modified stems and/or roots during two lab sessions early this semester - Lab Session #1 (Bulb Scaling, Scooping and Chipping) and Lab Session #7 (Geophytic Plant Propagation) - the content we cover today (bulbs, corms, tubers, tuberous stems, and tuberous roots) and Wednesday (rhizomes and pseudobulbs) should be familiar. My hope is that the conversations we have over the next several class sessions will support/strengthen the observations you've made during the lab sessions and will help make sense of the results you obtain when the above labs are terminated next Friday, April 14.

We'll end the class with the fourteenth quiz of the semester.

In addition to root sprouts, stolons, runners and several forms of natural layering, many otherwise stationary plants (what other kind is there, right) have evolved clever strategies for colonizing unoccupied space by growing horizontally instead of vertically. Many terrestrial plants (like the cannas and edible ginger we propagated last month), some marginal aquatic plants, and a few epiphytic plants (e.g., many bromeliads) accomplish this by means of modified primary, horizontal-growing underground stems called "rhizomes." Meanwhile, epiphytic orchids colonize trunks and branches of host plants by means of "pseudobulbs" that form along rhizome-like stems.

We'll end the class with a quiz (Quiz #15), and I'll return Monday's ungraded quiz (Quiz #14). You'll have until midnight this Friday evening, April 3, to email your score (between 0 and 10 as always) to me, using the Quiz 14 grading rubric and review video at this link.

Without a doubt this is always the most stressful lab session of the semester for me as we'll be building our own apple trees on dwarfing rootstocks using the "whip and tongue" grafting and "chip" budding techniques Steve Cummins introduced us to last week. Why so stressful . . . . ? Because we use VERY SHARP knives, in three of the past four years there has been at least one student getting the opportunity to experience their first stitches!

However, don't worry - too much. I do have one bandaid left over from last year - just in case;-)

We'll also tempt fate by performing top and approach grafting (at right, above) of tomato seedlings, as well as building our own "Ketchup 'n' Fries" plants!

Once we get all of the grafting out of the way, we'll terminate the "Clonal Propagation by Cuttings" exercises that we initiated back on January 17th during the first lab session of the semester.

I will also return Wednesday's ungraded quiz (Quiz #15). As always, you'll find a grading rubric and review video for this quiz here. Please email me your score (between 0 and 10 points) no later than midnight this coming Sunday, April 5.