Crops and Plants

Quite a few well-intentioned academics, more often than not in the social and ecological sciences, do us no favor by over romanticizing the pre-European contact past of Hawai‘i’s agriculture.

By Bruce Mathews, dean of the College of Agriculture, Forestry and Natural Resource ManagementUniversity of Hawai‘i at Hilo.

Sepia colored old print of valley with farmland.
He‘eia Valley, O‘ahu, 1910.
Bruce Mathews
Bruce Mathews

Hawai‘i rightly takes great pride in its rich agricultural history, the mālama ‘āina (deep care, stewardship, and respect for the land) of the Native Hawaiians, and no doubt much can be learned from the past. This being said, most conservation and resource management discussions in Hawai‘i pertaining to the revitalization of local agriculture tend to be far too insular, and focused on Eden-like interpretation of the past and anecdotal commentary for impactful progress to be made on viable paths forward. Yes, pre-European contact agriculture was self-sufficient, organic by practice, and did not rely on external inputs, however many bio-cultural, technological, and socio-political parameters have changed since that time. And there is strong evidence that pre-European contact agriculture and aquaculture had much greater impacts on Hawai‘i’s environment than previously thought (Kirch, 1982; Anderson et al., 2017). Native Hawaiian upland field systems based largely on intensive ‘uala (sweet potato) cultivation in the highly valued locations of greater natural soil fertility would have eventually run into sustainability challenges induced by gradual soil nutrient depletion (Vitousek et al., 2004; Hartshorn et al., 2006). In this regard it is also worth noting that no till aboriculture/agroforestry based on cultivation of ‘ulu (breadfruit) trees had some distinct environmental and subsistence agriculture advantages and should be further investigated (Rolett, 2008).

It’s time to test your soil!

By Chantal Vos, Researcher, and Norman Arancon, Associate Professor of Horticulture.

Norman stands in large sweet potato field.
Norman Arancon collects leaf samples from sweet potato field. Photo by Chantal Vos.

Sweet potato (Ipomoea batatas, L.) production along the Hamakua Coast can be increased by addressing nutrient imbalances in the soil. Sweet potato is an important crop in Hawai‘i both for local consumption and as an export crop and more than 90 percent is produced along the Hamakua Coast on the island of Hawai‘i (Miyasaka and Arakaki, 2010). Most commercial sweet potato farmers on Hawai‘i Island do not test their soil or crops on a regular basis for potential nutritional problems. Fertilizers are often applied indiscriminately based on prior experience or current practice from other growers, whether these areas have been cropped for many years or are newly cleared for cultivation. Soil fertility is often not optimal, even on land that has never been cultivated with sweet potato (virgin land). During crop production, available nutrients are lost through leaching, run-off, and crop harvest. Nutrient balances are distorted, and fallow periods have demonstrated limited capacity to adequately restore and build soil fertility. This being said, fallows will generally reduce many disease and pest problems (Bennett et al., 2012).

Garden tours given by UH Hilo ag students are a regular contribution to Earth Day Fair celebrations since the gardens were established in 2009 by former students.

By Norman Arancon, Associate Professor of Horticulture.

Student speaking to schoolchildren in the garden.
Lehua Patnaude, student of AG230, led tours in the gardens by the UH Hilo library lanai during the annual Earth Day Fair, April 20, 2018.

Some 205 students from local pre-K and high schools all over the Big Island toured the gardens by the University of Hawai‘i at Hilo Library Lanai during the celebration of this year’s Earth Day. The gardens were showcased by the Ag230 students of spring 2018. This has been a regular contribution of the class to Earth Day celebrations since these gardens were established in 2009 by former students.

Using the controversy over genetically-modified foods as its entry point, the film Food Evolution shows how easily fear and misinformation can overwhelm objective, evidence-based analysis. UH Hilo’s Prof. Shintaku weighs in.

Michael Shintaku
Michael Shintaku

Michael Shintaku, a professor of plant pathology at the University of Hawai‘i at Hilo, is among the many scientists featured in the film Food Evolution that tackles GMO (or genetically modified organisms) in food production. The film includes footage of Hawai’i Island and is narrated by Academy Award nominee Neil deGrasse Tyson.

Dr. Shintaku stated that in 2013, the County of Hawai‘i passed a bill banning transgenic crops (GMOs) from Hawai‘i Island, with certain exceptions (later reversed in federal court). This became a national story, attracting reporters from The New York Times and other media outlets.

If anything touches the small stiff hairs in the mouth of a Venus flytrap, the lobes on the plant snap shut, trapping whatever landed in the plant.

By Leilani Blair.

A worm inside the mouth of the plant.
Meal worm in Venus flytrap. Photo by Beatrice Murch via Wikimedia.

This carnivorous plant gathers nutrients from gases in the air and from the soil. The venus flytrap is native in parts of North and South Carolina. When the venus flytrap’s mouth is open wide you can see short hairs, these are called trigger hairs or sensitive hairs. If anything touches these small stiff hairs, the lobes on the plant snap shut, trapping whatever landed in the plant.

Turmeric, Curcuma longa, also known as Curcuma domestica and locally known as ‘olena, has been used for medicinal and culinary purposes for over 4,000 years.

By Maria McCarthy, Student, Bachelor of Science in Agriculture, animal science track.

Curcuma longa
The rhizome of Curcuma longa (turmeric, ‘olena). Also known as Curcuma domestica. Harvested on Maui, Jan. 2017. Photo by Forest Starr & Kim Starr via flickr.

The use of plants for medicinal purposes has been practiced since man has walked the earth. The practice has changed over the years, as well as the methods of propagating the plants.

Turmeric, Curcuma longa, also known as Curcuma domestica and locally known as ‘olena, has been used for medicinal and culinary purposes for over 4,000 years. The rhizome is the plant organ that contains all the sought out qualities.

One theory suggests that instead of food, the main focus became oil, since it is the biggest nonrenewable commodity. Another theory points to permafrost.

By Clarissa Zeller, Student, AG230, Sustainable Agriculture, Fall 2017.

Map of permafrost.
Map of permafrost in Alaska. Source: NSIDC.

Growing up in Alaska I knew that most food (not including subsistence) I ate was not Alaskan grown, but imported goods. The figures are about 96 percent imported and three to five percent locally grown, showing a great imbalance and reliance of foreign goods. It’s know by the government that Alaska only has three to five days of food supply in times of state of emergency. Also, to note that the cost of food varies greatly the farther away from major cities due to transportation fees and difficulties. In the community of Sand Point a pound of grapes costs $6.49, where the average in the U.S. is $2.88—this is just one example of a village/small town in Alaska.

The big question is: Why don’t Alaskans grow more of their food?

This tour was such a unique experience for me because I didn’t know much about cacao, but now I have a better understanding of what it’s like to process it.

Students gathered in orchard.
Alumnus Colin Hart talks to students about orchard airflow.

By Tiera Arakawa.

If you are looking for fun and adventure throughout the school year, a club to consider is the Agriculture Club. The Agriculture Club goes on adventures, tours, does projects that the students would like to do, and volunteers with various jobs of interest. Since my sophomore year of college, I have realized how important it is to get involved around the campus, find ways to give back to the community around us, and make long lasting friendships. For that reason, I decided to join the Agriculture Club because agriculture is what I am passionate about and I like to know that the little things that I do, especially volunteering is making a positive impact in our community.

In full circle, we were able to observe the work that these farmers had already done to shape their landscape, worked our hands in the soil and planted the cuttings that were harvested.

Students walking through taro patches.
Students make their way through six wetland taro patches.

We stood facing our hosts, our teachers for the day, the kua‘aina of the valley. Following traditional protocol, the chant Kūnihi ka Mauna presented us to Waipi‘o Valley, and more specifically Ka‘ilipu‘ueo. ʻAma Lilly, vice president of the University of Hawai‘i at Hilo Agriculture Club, lead us in this chant. It allowed the club not only to present themselves in reverence to a place rich with Hawaiian traditional legacies but also helped to set the tone for the day ahead.

The entire breadfruit tree is a multipurpose and useful resource.

By Damon Adamson.

Belonging to the Moracceae (Fig or Mulberry Family), breadfruit or ‘ulu in Hawai‘i encompasses four primary sub-species: Artocarpus altilis, Artocarpus incisus, Artocarpus mariannensis or Artocarpus communis. Grown in the Hawaiian Islands, as well as throughout the Pacific Basin area. They have been hybridized and many diversities have become prolific. There are currently 24 distinct species of breadfruit. Fruit size, shape, coloration, seeded or seedless, and seasonal ripening are a few of the differences.