Honors Research Trip December 2008 By: Chelsea Robinson In December of 2008, five undergraduates traveled to Oahu with Dr. Thomas Gillespie as part of a research group studying the deciduous forests, continuing his study of this forest type on islands of the Pacific. The trip was centered on several re-vegetation sites on the island as well as invasive species removal. We removed non-natives and planted at a site within Koko Crater as well as in a backyard of a graduate student that was on state land. The group included Dr. Gillespie and five undergraduates who had all been in the course Geography 111, Forest Ecosystems, at UCLA. Tropical dry forests are among the most endangered ecosystems worldwide and the Hawaiian forests of this type are especially threatened. The island of Oahu once was inhabited by many endemic and native species but has suffered an exceptional loss of habitat, primarily due to colonial powers. The islands were colonized by two separate powers, by the Polynesians around 300 BC and by the British Captain Cook in 1778. More than 25% of the endangered plant taxa in the entire Hawaiian flora are from dry forest or dry scrub ecosystems and approximately 20% of taxa from these habitats are known to be extinct (Sakai et al. 2002). Despite its extremely endangered status, this ecosystem has been studied very little and there is a lack of information regarding the feasibility of reforestation of native vegetation. With more than 98% of the original forest extent removed, it is important that Hawaiian tropical dry forests Clearing invasive species from Diamond Head receive more attention to begin the re-introduction of native flora. We arrived the evening of December 12, to our first Hawaiian rainstorm. Because we arrived late at night, we could not begin our research work until the following day. Instead, we checked into our hotel and got some rest. On Saturday, 12/13, we went to different botanical gardens around the island of Oahu. The first place we visited was the Foster‟s Botanical Garden. While many of the plants there were unique and beautiful, we had a hard time finding any natives! Finally we found several trees from the native genera Pritchardia. The next botanical garden we visited was Lili'uokali botanic garden. This garden had many different native species, including several of the species I had Diospyros sandwicensis previously ordered for my study site, including Lama (Diospyros sandwicensis), Naio (Myoporum sandwicensis), and two species of native hibiscus. While these native plants were planted and did not occur unassisted at this site, they were still some of the only natives we saw that day. Next, we tried to visit the Lyon Arboretum, managed by the University of Hawaii at Manoa. However, while it had only been Myoporum sandwicensis sprinkling that morning, as we made our way up the hill to the arboretum it began to pour. We stopped in the visitor office, and we talked to the man who worked there, who said they closed in under 10 minutes! We were able to do a quick trip through the start of the arboretum, but we did not get to explore too much. The trails were narrow and steep and with the rain were slightly precarious. After spending the morning visiting various botanical gardens, we stopped at the National Memorial Cemetery found in the Punchbowl crater. Here we were able to see down the outside 2 of the crater on the dry side, where dry forest would naturally occur. Instead, we saw a lot of invasive Leucaena leucocephala, also known as haole koa, which we ended up seeing much more on the trip at different sites. This species, native to Mexico, is particularly invasive because it can grow quickly into dense thickets which crowd out native vegetation. As we left Punchbowl Crater, we decided to head to Koko Crater to look for a suitable site for my native revegetation project. On our way, we saw some street vendors selling Filipino and Hawaiian food. We jumped at the chance to try roadside native food, so we stopped. We received pork adobo with rice and macaroni salad for the Filipino food, and green squid mush, glass noodles, salmon salad, and pudding for the Hawaiian food. We all thought it was pretty tasty, until a few hours later, we all became a little nauseated. We then continued on our way to Koko crater. The rain had eased up, luckily, so we began on the easy hike through the crater. Our luck with the weather, however, turned sour 30 minutes into our hike. We were able to experience our first true tropical storm in the best way ever- in shorts and sandals! We had not quite found the place to plant for my study yet, so we continued on our way, walking almost 45 minutes in the rain. On Sunday, 12/14, the Honolulu marathon was conducted right outside our hotel. While exciting, it meant there was no way possible to take a car out for the day to explore other sites. Instead, we decided to hike to the Diamond Head crater, the symbol of Oahu. We were staying relatively close to the site. Before heading into the visitor area in the interior of the crater, we scouted some possible re-vegetation sites on the Dr. Gillespie on the outer outside of the crater. We found some suitable spots that looked like rim of Diamond Head 3 they might have once been a riparian area, near a stream. After doing some scouting, we continued our hike around the exterior of Diamond Head to the tunnel which allows entry to the interior of the crater. Once inside, there are informational signs discussing the history of the crater as a military base, the formation of the carter, and the fauna we would expect to see on the hike to the peak. The hike from the base to the peak was 1.6 miles round-trip. The hike up allowed us to see many non-native plants, including haole koa and buffalo grass. Both of these invasives covered the interior and exterior of the crater. Diamond Head crater was used as a restricted military reservation from 1906 to 1976. In 1976, a portion or the interior of the crater was opened for recreational use, and one trail up to the peak was opened. Over a million visitors each year come to hike up the old military trail to the peak, where a military bunker still sits. While the public is allowed in some of the crater, much of it is off limits. The restricted areas are used by Civil Defense, FAA, and Hawaii National Guard. Diamond Head was declared a National Monument in 1968. Monday December 15, we met with Matt Schirman, the owner of the Hui Ku Maoli Ola native plant nursery on the windward side of the island. I had previously corresponded with him through email and had ordered about 100 native plants for our re-vegetation purposes. At his nursery, we saw more native Hui Ku Maoli Ola Nursery Hawaiian plants together than the rest of the trip. After Matt showed us around the native plants he was growing, he took us to a 20-acre plot he had recently purchased adjacent to his nursery. He was calling it the “Papa hana Kuola” 4 and was converting it to a cultural center. They were fortunate enough to have a natural spring that even had fish living in it, with water fresh enough to drink. With the water from this spring, Matt was planting Taro plants there as a cultural education center. While not a plant native to Hawaii, Taro is considered naturalized as it was introduced by the Polynesians around 300 BC. We settled on picking up some of our ordered plants the folowing day since we had a meeting to get to. We had an appointment to meet with the Park Coordinator for the Diamond Head state monument, named Yara Lamdrid-Rose. We were hoping to get her permission to have a re- vegetation site for our project within the crater. Yara had a very pessimistic view of our chances with a site there, as many projects have failed in the past. She explained to us that many fail without proper maintenance in the long term. She also drove us through several restricted areas to show us past failed projects. One of the „failed‟ sites still had a good population of several native species, including Gossypium tomentosum, also known as Mao and Hawaiian native cotton. While she did not allow us to begin a new re-vegetation project there, she did eventually agree to letting us clear the invading grasses and haole koa of the site with native cotton, so we spent Wednesday there. The following day, we decided on planting for the project at the Koko crater site. We picked up 30 plants from Matt‟s nursery: Diospyros sandwicensis – Lama 8 plants Myoporum sandwicensis – Naio 5 plants Hibiscus brackenridgei – Ma‟o hau hele – 5 plants Psydrax odorata - Alahe'e 7 plants Reynoldsia sandwicensis – Ohe 5 plants Koko Crater Study Site 5 We decided on a site within the Koko crater that was on a slope near a ravine, with plenty of soil and shade. Native species were growing nearby including Wiliwili, Lama, and several native hibiscus species. From the direction and incline of the slope, we determined which side would be moister. The plants that we had that did better in moister soil were the Diospyros and the Psydrax. In contrast, the plants that needed drier soil were the Reynoldsia, Myoporum, and Hibiscus brackenridgei.