Bees and Beetles

Tropical Gardening

About Bees and Beetles

To a person who prides herself on being a serious gardener, the tropical rainy season is a mixed blessing. While there should be time freed up because there is no need to water plants, the explosive growth of all the fauna requires twice as much effort just to keep the yard from being overtaken.

So I happily spend hours each day elbow deep in vegetation with a clipper in hand. It is while pruning away that I have come up close and personal with several species of bees that are quite interesting, and luckily for me, don’t generally sting unless you disturb the nest.

Don’t let the name mislead you, the Orchid Bee and Carpenter Bee enjoy lots of different varieties of blooms. They both are very large bees, averaging about 1.5 inches (5 cm) long with chunky, smooth bodies. They first started appearing en masse in early May, and now that the breeding business is done, it is more common to see lone bees feeding.

Both species reside in the Riviera Nayarit as they prefer the tropical and subtropical regions of the western hemisphere. Unlike their cousins the bumble bee, the subspecies that have staked out my flowers are a unique shiny black. For weeks I have tried to get close up pictures but it seems like they sense the camera- I would sit for an hour with camera in hand, nada. But if I’m busy trimming on a ladder, here they come! I also collected carcasses to study and identify the species.

The orchid bee (above two photos) is one of the most brilliantly colored insects, and may appear metallic green, blue, purple, gold, or red besides black. Orchid bees are fast, strong fliers and can travel great distances. Some are known to fly as far as 45 to 50 km (28 to 31 mi) in search of flowers. A close relative of the bumble bee, it has a long tongue that allows it to reach nectar deep inside tropical flowers. Orchid Bees are dependent on pollen as a protein source and on flower nectar or oils as an energy source.

Adult females collect pollen primarily to feed their larvae. The pollen they inevitably lose in going from flower to flower is important to plants because some pollen lands on the pistils (reproductive structures) of other flowers of the same species, resulting in cross-pollination. Bees are therefore a good thing to have in a flower or vegetable garden. Orchid Bees have a hairless head with antennae; compound, wide spread eyes, jaws, a proboscis (mouth structure) with tongue for nectar gathering.

One interesting fact about the Orchid bee is that the male spends most of his time flying around the nest playing guard. This is ironic as nature has left him ill prepared: he has no stinger! Only the female can sting.

Unlike the insidious carpenter ant, which is a nuisance that can damage property, the Carpenter Bee generally chews plant stalks or tree branches to house its nest- they definitely do not like painted or treated wood of any type. Carpenter bees are mostly large, metallic-colored bees that have 730 species.

They live throughout the world wherever woody plants abound, especially in forested regions, with the most species living in the tropics. Carpenter bees typically fly long distances and visit many kinds of flowers, preferring the tubular type blossoms of the blue trumpet vine, Brazilian flame, and alamadra vine-all that grow very well in our location. In this species, the females are entirely black and the males are black with whitish markings on the face, (note photo below.) Both males and females are larger than bumble bees.

Early in the spring the males establish territories that they patrol and protect zealously not letting other males come near; in fact often they chase away almost anything that moves including unsuspecting gardeners.

Sometimes they choose territories near promising nesting sites not because they plan to set housekeeping but because they know that such places will attract females. The females have powerful jaws and can dig holes in soft wood to make their nests, hence their name of carpenter.

Beware the Beetle:

While the presence of bees is a plus for a healthy garden, it is not the case with beetles. Beetles are by far the largest orders of insects, with 350,000–400,000 species in four suborders, with many of the species extremely detrimental to plant health.

One of the worst local offenders is an insect called Picudo Prieto or Mayate Prieto (Rhybchophorus palmarum L.) that can grow to nearly 4cm (1.5 inches) in length. What makes the Palm beetle such a concern is that the female tunnels into the crown of the palm, laying 50-200 eggs. The yellow larva hatch and proceed to bore holes throughout the trunks of dead and dying palms to feed and pupate.

Adults emerge three times each day to mate and feed. During this process, it is not unusual to hear both adults and larvae chewing inside palm trunks from several feet away. The outcome for the host palm is certain death.

Since I live in an area that is home to both wild and cultivated palms, this is a serious issue. While homeowners with any type of palm tree should be vigilant, the bad beetles prefer the species of Bismarck, Coco de Agua and Coco Aceite, but will move in on weakened, stressed palms of other types. It’s a good idea to fertilize, trim, and regularly spray the crown of your valuable palms as prevention.

The people of the Riviera Nayarit first became aware of this problem due to the efforts of long time resident Sarah Walker, who has gone to battle with the black invaders. She first noticed a problem with one of her huge specimen Bismarck palm trees, which has now died. She franticly sought help from palm expert Benjamin at Los Palma plant nursery and a government agricultural agent in Tepic.

The research indicates that an infestation is 4-5 beetles a day per trap; Sarah said, “My trap on the property caught 10-20 beetles a day. If Mexico doesn’t do something about the palm beetle, they will destroy all the palms in Mexico in eight years. They are that destructive!”

Sarah has set up and regularly maintains 10 yellow palm bee traps throughout La Penita and Guayabitos in an effort to control the spread of these beetles. She supplied the left photo that shows the adult and a larva.

The key to a successful garden involves knowing the good bug from the bad; prevention is always better than trying to halt an infestation after the fact.