Nate’s Adventures: Revisiting the Native Dry Forest Restoration Project in Pia Valley

By Nate Yuen, Chapter Outings Chair | Reading time: 3 minutes

I joined Protect & Preserve Hawaiʻi in January 2022 to see the progress being made to restore the native forest in Pia Valley on the west end of Niu Valley. Tyrone Montayre is the landowner and the founder of the non-profit that is bringing back the native dry forest. The Pia Valley reforestation project initiated in 2019 and considerable progress has been made in just 2 years.

I arrived late and caught up with the tail end of the group who were carrying plants to the restoration site. In addition to plants, the group carried tools, fertilizer, and water to the restoration site in Pia Valley.

Over 30 people showed up for the work day. With a group this size showing up consistently each month, considerable strides have been made to restore the native ecosystem.

Virtually all the plants made it through the dry season. The effort to dig out the root balls of guinea grass paid off as many native plants are taller than the grass. Many native trees, 4-5 feet high, are growing above the grass. One kou tree in particular is growing tall and putting out lots of leaves.

The water catchment system was useful to nourish the plants during the driest months. But since the plants were selected for their ability to tolerate dry conditions, very little watering was actually necessary.

The plan for the day was to concentrate on the lower sections of the restoration area close to the stream. With the arrival of hoʻoilo -- the wet season -- water was flowing in the stream.

A wall is being built near the stream using uhau humu pōhaku – traditional Hawaiian dry stack masonry. Great to see so many stones were aligned to construct the wall.

Tyrone Montyare welcomed the group and Miles Thomas gave a fascinating talk about how native plants in Pia valley are faring.

Part of the work involved cutting down invasive trees like Christmas Berry. The trees were shading the restoration area so we cut as many as we could.

This part of the valley is shaded by large trees so the understory is green and mossy. We also removed guinea grass and other invasive species that were choking out the native plants we want to grow.

After invasive grass is removed, we laid down weed mat — a heavy woven plastic burlap mat — to block sunlight and stop weeds from growing. Holes were cut into the weed mat for the baby plants we put in the ground. There were lots of holes to dig in the weed mat.

Many thanks to Hui Kū Maoli Ola who donated 140 native plants for today’s work day. About 1,700 plants have been planted at this site to date – most provided by Hui Kū Maoli Ola.

Great to see the community mobilize and participate in tree planting. Many hands make the work go by fast.

Much of the invasive haole koa trees are being kept for now to shade the new plants until they become established. When the native plants become established we will cut down the haole koa.  We will need to pull out the roots otherwise the haole koa will grow back.

There were so many people that it did not take long for all 140 plants to be planted and watered.  Tree plants are held on the 3rd Saturday of each month at Pia Valley. If you would like to participate in this community effort to bring back the native dry forest in Pia Valley, you can sign up at protectpreservehi.org.