This semester, my botany 101 students collected leaf and flower specimens from around the UH West O’ahu campus to learn how herbarium specimens are collected and preserved. They turned out so well and we all had so much fun that I wanted to show them all on my blog!!
Step 1: collect plant material
We didn’t collect in the student organic garden, since we didn’t want to defoliate any of the plants the students are working with in the garden, so instead we stuck with the landscaping around the campus grounds. Fortunately, the majority of plants on West O’ahu’s campus are native or of Polynesian origin.
A selection of flowers collected by the students
Step 2: learn about the plants
The only plant around the campus grounds that was universally known to the students was the Hibiscus – not surprising since ma’o hau hele (yellow hibiscus, Hibiscus brackenridgei) is the state flower! The others required identification from a Hawaiian flora identification guide. We used the guides to identify the species, determine whether or not it is native to Hawai’i, and learn some interesting facts about its biology and ecology.
No matter how many books I bring in, they always prefer their phones, ha ha ha ha ha
Step 3: press the plant material
Prior to long-term preservation, it is important to remove the water content of the tissue. There are a number of ways to do this. We used plant presses. You lose the 3-dimensional structure of the flower, but they are easier to store. Also, they just look so pretty 🙂
In botany, we use zoology textbooks as paperweights
Step 4: preserve the specimen for curation
Once the plant parts were fully pressed (we left them for ~5 days), we removed them from the presses and arranged them on cardstock, which we then covered with clear contact paper. Each specimen was given a unique identification code, labeled with the species name, collection date and location, and collector’s name.
Step 5: enjoy your beautiful specimens!!
Many students chose to keep their specimens, others donated their specimen to the brand new UHWO Herbarium Teaching Collection, which exists as of right now 😀 I look forward to adding to the collection every semester!
Laci M. Gerhart 