The effect of liquid bio-organic fertiizer on the productivity of ironwood (Eusideroxylon zwageri) leaf biomass

Abstract

Ironwood (Eusideroxylon zwageri) is an endemic species in East Kalimantan known as ulin by the local community. Ironwood is a protected and slow-growing species. It is essential to look for an alternative use in less period. Ironwood young leaves have been used traditionally as a decoction with diuretic and hair-blackening properties. Such usage provides an opportunity to utilize ironwood without cutting down trees. As a reason for leaves sustainability, it is necessary to stimulate the formation of leaves, one of which is to use liquid bio-organic fertilizer. This study aimed to determine the effect of liquid bio-organic fertilizer on increasing the growth and yield of young ironwood leaves in nurseries. Fifty ironwood seedlings were given 5 ml of liquid bio-organic fertilizer every month, and the other 50 seedlings were not given any fertilizer. The number of young leaves was recorded in the third and ninth months, while the young leaves were harvested in the sixth and twelfth months. This research showed that liquid bio-organic fertilizer increased height increments by up to 107.58%, diameter increment by up to 20.36%, the number of iron wood shoots up to 184.62%, and it also increased the weight of young leaves that can be harvested by up to 588.89%. There were any differences effects of liquid bio-organic fertilizer applied with and without bio-organic fertilizer on the growth and yield of young ironwood leaves. Ironwood shoots’ growth and yield by application of liquid bio-organic fertilizer are better than nonliquid bio-organic fertilizer.