I am quite familiar with the molave tree (Vitex parviflora Juss.), also called small-flower chaste tree,  molawin, tugas, and many other vernacular names.

At least I am confident enough that I can identify the tree in any size, on field or on a pot, including stocked logs and posts, with respectable accuracy.

I’m likewise familiar with the two strains or types growing in the province of Sarangani and in General Santos City, Philippines, known locally as the tugas babae and the tugas lanhan.

However, whether the two are simply botanical variants of the same species or they are distinct species need further enlightenment from plant taxonomists.

In this paper and elsewhere in this site, the use of the term strain and type are merely for convenience and does not connote an expert determination of the issue.

Read more

The molave tree (Vitex parviflora Juss.) is a plant belonging to the family Verbenaceae.

It is a close relative of the five-leaved chaste tree or lagundi (Vitex negundo).

Also called molawin and tugas, it is a medium- to large-sized, drought-tolerant, hardwood tree which is indigenous to the Philippines and other Asian countries. It has multiple uses.

In Sarangani, Philippines, these trees naturally grow on limestone, sinking their roots into crevices.

Two types are indigenous in the province. One is locally called tugas babae (“babae” is Filipino word for woman). The other type is called tugas lanhan (“lanhan” means oily).

Read more

What comprises the agronomic crops?

There is no unanimous agreement, but there is wide support that the species in each of the following plant groupings belong to the domain of agronomy:

• cereal or grain crops;
• grain legumes or pulses and oilseed crops for food, feed, or industrial use;
• pasture and forage crops;
• fiber crops;
• sugar crops;
• and starchy root and tuber crops.

From the different divisions or branches of horticulture, the horticultural crops consist of the olericultural or vegetable crops, pomological or fruit crops and edible nuts, floricultural and other ornamental crops, and nursery crops.

In addition, the aromatic crops and the medicinal crops are generally included.

The ornamental crops are further grouped into flowering and foliage plants which are grown for special purposes such as for cutflowers, potted plants, landscaping, interior decoration, or floral arrangement.

Read more

Light intensity or light quantity refers to the total amount of light that plants receive. It is also described as the degree of brightness that a plant is exposed to.

In contrast to light quality, the description of the intensity of light does not consider wavelength or color. 

The intensity of light is usually measured by the units lux (lx) and footcandle (fc).

One footcandle means the degree of illumination 1 foot away from a lighted standardized wax candle; 100 footcandles is 1 foot away from 100 candles that are lighted simultaneously.

Lux (pl. luces) is the unit of illumination that a surface receives one meter away from a light source.

One footcandle is equal to 10.76391 luces and 1 lux is approximately equal to 0.093 footcandle.

Read more

Stephen Hales (1677-1761).

Often referred to as the founder or father of plant physiology (Devlin 1975; Hopkins 1999; Egerton 2008), Hales pioneered quantitative physiology.

He was born in Kent, England, and studied theology at Cambridge, but also read mathematics, physics, and botany.

He became a clergyman but also devoted much of his time to scientific pursuits, particularly in the conduct of experiments in plant physiology. 

His most important work, Vegetable Staticks (published in 1727), was in plant physiology.

He suggested that plants derive something from the atmosphere (Rook 1964), a guess that future researchers have proven correct and has become an essential component of the process of photosynthesis in plants.

Read more

There are many fruit types depending on the criteria under consideration.

The plant organ called fruit in the angiosperms may be classified according to the number of ovaries incorporated in the structure, origin of development, nature and structure of the pericarp, ability of the fruit to split apart when mature and the manner in which this occurs, and the attachment of the seed to the ovary.

According to the number of ovaries in the structure, there are three fruit types: simple, aggregate, and multiple.

Simple fruits are most common in the angiosperms.

Read more

Various terms on plant classification are here reviewed grouping and describing plants according to their natural habitat or ecological adaptation.

These terms facilitate communication and understanding about agricultural crops or potential crops for various purposes such as crop selection for gardening or crop farming, research and development, and plant collection.

Substantial understanding of plant classification and plant adaptation is likewise important in applying more efficient methods for the commercialized production of crops.

In The Plants (1963), there is mention that the pygmy cedar (Peucepyllum) has the unique ability to live without soil water.

It replenishes its water supply from the water vapor in the air at night time.

This is amazing because it is always presumed that terrestrial plants naturally obtain water from the soil.

After all, terrestrial plants have roots which are anchored on the soil.

Read more

There are three types of transpiration, the process in which water is lost from plants in the form of gas or vapor: stomatal, cuticular, and lenticular.

These are briefly described below.

1. Stomatal transpiration

Among the three types of transpiration, this is the most dominant being responsible for most of the water loss in plants.

It accounts for 90-95%  of the water transpired from leaves.

As the name suggests, the process involves the participation of the stomata (sing. stoma) or stomates, microscopic pores in the epidermis of the leaves.

Liquid water is first absorbed by the plant through its roots from the soil.

It is then translocated via the xylem tissue in a continuous stream towards the mesophyll cells of the leaves.

Either at the surfaces of the mesophyll cells or of the epidermal cells close to stomata, liquid water is converted to water vapor.

It then escapes through the stomatal pore at the time when it is open to allow entry of CO2 and release of O2. 

Read more

Kaong propagation requires the use of seeds. Wildlings can also be collected from forest floor or under the canopy of mature plants.

These methods, including pregermination treatments before seeding, have been widely used in many palm species such as anahaw (Livistona rotundifolia), buri (Corypha elata), Macarthur palm (Ptychosperma macarthurii), royal palm (Roystonea regia), yellow palm (Chrysalidocarpus lutescens) and rattans.

This is so because these plants and kaong (Arenga pinnata), also called gomuti and sweet palm, belong to the same botanical family Palmae or Arecaceae. These palm plants share common characteristics which affect plant propagation.

Read more