We have been working hard at restoring the native forest at our site along the Manoa Cliff trail. While there has been great strides since the project started in 2005, the trail itself outside our area still has some great native plants.
The flora on Pu’u Ohi’a has been described in the past; by Dr. Raymond Fosberg and again by Beth Saxon. I am nowhere near their level, but the plants still are. Sure, the trail is highly degraded, but here is another chance for the plants to shine.
After walking through all the non-native plants through the first climb, at the metal grated walkway you reach the 2 stalwarts of the Hawaiian mesic forest. Pictured above is Ohi’a Lehua (Metrosideros polymorpha) with Koa (Acacia koa) in the background. As overrun the understory is with non-natives, Ohi’a and Koa trees still overshoot the top in many locales on the trail.
Hulumoa, Hoi Kuahiwi… why not keep the “What grows on Bobea?” meme going. Here ‘Ie’ie (Freycinetia arborea) is growing scandent on ‘Ahakea lau nui (Bobea elatior). In many places on the trail, ‘Ie’ie grows as ground cover as well. See below:
Some of the most conspicuous native ferns are Hapu’u (Cibotium chamissoi), Pala’a (Sphenomeris chinensis), and Uluhe (Dicranopteris linearis).
Something a little different about the Manoa Cliff trail is that you don’t find many areas where Uluhe is well established. Here is really the only spot where Uluhe grows vigorously like in the rest of the Ko’olaus. This area had a landslide roughly 7 years ago. I don’t know if Uluhe was growing there beforehand, but it has certainly taken advantage of the opportunity.
If you look closely, you can see that there are a couple specimens of mountain naupaka (Scaevola gaudichaudiana) below the landslide area. They must have become established sometime in the intervening 7 years. It is nice to see that natives aren’t completely out-competed by fast growing weeds.
Here are the 2 species of Kopiko (Psychotria spp.) found on the Manoa Cliff trail. Although hopefully Psychotria hexandra is still waiting to be found. Kopiko (P. mariniana) typically has much more conspicuous domatia (the little bumps along the midribs pictured to the left) than Kopiko kea (P. kaduana). The easiest way to tell the difference though is with the infloresence. In P. kaduana, the peduncle is much longer and tends to droop more than in P. mariniana.
By the bench at about the halfway point to our restoration site, you’ll find a couple specimens of Lehua ahihi (Metrosideros tremuloides). From this point on you’ll start noticing more and more native plants.
Including these bad boys. We are very lucky to have a grove of healthy Haha (Cyanea angustifolia) right along the trail.
Aside from the lack of Uluhe, the Manoa Cliff trail is also known for its large number of Koki’o ke’oke’o (Hibiscus arnottianus). There is rarely a time when you won’t find at least one tree in bloom.
Just before you reach the restoration site, there is a gulch that is botanically pretty cool.
There is a good number of Mamaki (Pipturus albidus) found in this area. Mamaki seems to be holding its own, with seedlings coming up in various places.
Also, literally right next to some of the Mamakis, are 2 different species of Cyrtandra. This genus, at about 52 species, is one of the most speciose in Hawai’i. It’s right up there with Melicope and Cyanea.
This one is Cyrtandra grandiflora. I have yet to see one flowering, but I would like to see if it lives up to its name!
And here is the other species, Cyrtandra cordifolia. This species is neat because the new growth and the lower surfaces of the leaves is covered with dense, velvety hairs that is soft to the touch.
The last thing I wanted to show is this Kalia (Elaeocarpus bifidus). While it does bear fruit often, it is also carrying several Hulumoa (Korthalsella complanata).
I’m pretty sure it’s not the same tree, but Dr. Fosberg mentions Korthalsella on Elaeocarpus in his field guide as well. It would be neat to have that direct link to the past. At this point, I can only imagine what the forest looked like when he was writing his field guides. But who knows, with all the hard work that is being done, perhaps the forest of the future will have an even greater complement of native species than even what Dr. Fosberg saw all those years ago.