Category Archives: Plants

Tree tobacco

Tree Tobacco (Nicotiana glauca) heralds from South America, but in Hawaii, it’s an invasive species.
Tree Tobacco (Nicotiana glauca) heralds from South America, but in Hawaii, it’s an invasive species. The chances of eradicating it are slight. Controlling its spread is a more realistic possibility. But tree tobacco is one invasive species in Hawaii that does have something going for it.

Enter Blackburn’s sphinx moth (Manduca blackburni), a large, endemic moth, once thought extinct, and a long-time resident on the endangered species list. Among its problems is that its host species, ‘aiea, (Nothocestrum spp.) has been on the decline for a while. ‘Aiea belongs to the nightshade family (Solanaceae) as does tree tobacco.

It seems that the moth, in the interests of survival, decided tree tobacco is not so bad. So we have an endangered species becoming reliant on an invasive species. Hmm. As I said, control is the most likely approach with tree tobacco and that will undoubtedly involve checking to see whether Blackburn’s sphinx moth is present before removing areas of tree tobacco.

That’s good news for the plant in this photo. I found it at Pu’u Wa’awa’a, a State Forest Reserve on the northern slope of Hualalai. Pu’u Wa’awa’a is home to a variety of endangered plants and animals including Blackburn’s sphinx moth.

For more information about tree tobacco, go to cabi.org/isc/datasheet/36324.
For more information about Blackburn’s sphinx moth, go to fws.gov/pacificislands/fauna/bsmoth.html.
For more information about Pu’u Wa’a Wa’a, go to puuwaawaa.org.

Mauna Loa silverswords bloom and die

A silversword blooms on Mauna Loa.

This is the time of year when silverswords bloom. These plants, members of the sunflower family, are endemic to Hawaii. There are slightly different silverswords growing on Mauna Loa, Mauna Kea and Haleakala on Maui. The plants are very susceptible to root disturbance and the activities of goats, pigs and humans has led to their decline. They’re making a comeback now thanks to fenced enclosures and careful management.

These photos were taken on Mauna Loa a few years back. The flower stalks were about 6 to 8 feet tall. The plants live for up to 30 years, but once they bloom, they die (like the one in the background of the top photo).

In the second photo, the ongoing eruption of Kilauea’s Pu’u O’o vent can be seen.

For more information about Mauna Loa silverswords, go to nps.gov/havo/learn/nature/endangered_ahinahina.htm.

A silversword blooming on Mauna Loa with Pu'u O'o vent erupting in the background.

Prepare to pupate

A Hawaiian monarch butterfly caterpillar preparing to pupate.A Hawaiian monarch chrysalis attached to a ti leaf

This Hawaiian monarch butterfly caterpillar was getting ready to pupate. It attached itself to the underside of a ti leaf with a silk pad. Just a few hours later it had molted into the blue-green chrysalis to the left.

Only a small percentage of monarch eggs make it all the way to adulthood, so I hope the geckos don’t get to this one. I’ll keep an eye on it over the next week or so.