We climbed up Kuliʻouʻou West to the summit, hiked along the spine of the Koʻolau Mountains to Hahaʻione, and dropped back down to loop back where we started.
Starting from the end of Kalaʻau Place in the back of Kuliʻouʻou Valley, we took the left fork that leads to the Board of Water Supply pumping station rather than the right fork that leads to the regular State Trail. Just to the right of the pumping station is where we started our climb up Kuliʻouʻou West — the ridge that forms the west side of Kuliʻouʻou Valley.
Justin Ohara and I made our way up the trail through tall grasses, strawberry guava, lantana, and other invasive plants as it climbs to the top of the ridge.
We stumbled on a number of mountain ʻilima (Sida fallax) shrubs with yellow-orange blossoms almost an inch across as we climbed ever higher.
When we gained the top of the ridge we rested under the shade of iron wood trees whose needles carpeted the ground. After enjoying cool mountain breezes, we continued towards the summit through formosan koa trees that lined the trail.
We came across a number of white flowers of naupaka kuahiwi (Scaevola gaudichaudiana) whose petals are all on one-side giving the appearance that it is just half a flower.
After climbing up through a section dominated by ʻuluhe ferns along the margins of the trail, we continued climbing towards the summit.
The higher we climbed the more native the vegetation became. When we reached the steep eroded section, we appreciated the many footholds that allowed us to climb up without difficulty.
From our vantage point near the top of Kuliʻouʻou West we had a commanding view of Hawaiʻi Kai, Koko Crater, and Koko Head — the eastern most point on Oʻahu. We were also pleased to see the bright red flowers of lehua papa (Metrosideros rugosa).
When we reached the summit, we peered over to the windward-side of the island and saw thick clouds over Kāneʻohe Bay. We noticed that the Waimanalo Reservoir which had refilled during the rainy season was low once again. Apparently, the rainfall has been light over this part of the island in recent months.
One of the more unusual native plants we noticed along the edge of the Koʻolau was kolea (Myrsine spp.) which provided a nice resting spot for a bug.
We hiked from peak to peak and climbed up and down along the spine of the mountain as we made our way to Puʻu O Kona.
Not far beyond Puʻu O Kona we saw a rare Lobelia hypoleuca with multiple spikes of blue-purple flowers. Many thanks to August Smith — who tipped us off that he saw this plant in bloom during his Piliwale-Makapuʻu adventure — we knew where to find these rare native flowers.
Although the most impressive flower spikes were past their prime and were going to seed, there were a couple of small inflorescences that were still in bloom. I was thrilled to examine the rare flowers up close.
Proceeding onwards, we continued along the very edge of the Koʻolau Mountains climbing up and down the spine of the mountain.
When we reached the summit of the State’s Kuliouou Trail, we opted to continue along the spine to see what else we might encounter along the edge of the Koolau.
We were pleased to see a number of lehua ahihi (Metrosideros tremuloides) in bloom. It was interesting to see how different the leaves and stems of the plant differed from the lehua we had seen earlier in the hike.
While making our way along the edge, we looked back on Puʻu O Kona and could see Mokapu Peninsula and the Mokulua Islands along the coast.
Beyond the Kuliʻouʻou summit, a number of sections along the Koʻolau spine are forested with ironwood, christmas berry and other invasive trees. After passing a series of electrical towers, we reached Hahaione and turned right to descend the ridge which was covered with ironwood trees.
While making our way down the ridge to loop back where we started, I reflected on the great time I had climbing up Kuliʻouʻou West and along the spine of the Koʻolau Mountains to Hahaʻione where we saw a number of native plants and flowers. What a great hike!
Native Hawaiian Plants, University of Hawaii, Department of Botany
Plants of Hawaii, Hawaiian Ecosystems at Risk