Harvest Nam Dok Mai Mango

Nothing can compare to a fully-ripened, organic-grown fruit! 

I am very satisfied with my Nam Dok Mai Mango tree! This is it's first debut and it has born 14 fruits! I have harvested 4 of them so far. And they are all satisfactorily sweet and juicy!

In my previous post on my Nam Dok Mai Mango Tree I said that my tree suffers from leaf gall midge disease, which was contracted while it was still in the nursery. Midges are very small flies in 1-2 mm in length. They lay eggs into the tissue of young leaves, leaving a small reddish spot which becomes swollen and soft, where the gall formation begins within 7 days and attains a diameter of 3-4 mm. Adults usually emerge from the underside of the leaf, leaving the pupal skin protruding from the emergence hole. The galls on the mango leaves will result in reduced photosynthesis, leading to leaf drop and lowered fruit production. Younger trees may die while older trees fail to recover normal growth after repeated attack. There are no examples of eradication of the insect anywhere in the world.

I experimented with my only organic way of eradicating this pest. It's only by poking the wart-like galls and then using a sharp object, usually my shears, I pierce through the spot, leaving a small hole.

My main purpose is to kill the insect in the pupal stage in order to prevent it from growing mature and infesting the whole tree. And so far I am successful! Of course this wouldn't be easy for mango trees grown in ground, as it can reach heights of 6 m or more but for container-grown trees this way is sufficient.

I don't encase the fruit with plastic bag this time, and so far my mango fruit are growing healthy and not attacked by fruit flies.

Handling Leafminers

I've been noticing some squiggly white lines on my tomato leaves since last week. It started with one or two leaves, but then today, I realized it had expanded to more leaves, even to my younger seedlings! At first, I thought it was the watermark caused by careless watering, but I couldn't assuage my curiosity and decided to do some scrupulous research and was quite surprised with my findings. It's not trivial at all! 

Leafminers are actually the larval (maggot) stage of many insects such as flies, moths, sawflies and beetles. The female adult flies lay their eggs on the surface or undersides of the leaves. 

Life Cycle: Mature larvae overwinter in the soil under host plants. As temperatures warm in the spring larvae pass to the pupal stage and appear as young adults in late April. Mated females use their needle-like ovipositor to lay up to 250 eggs just under the surface of the leaf epidermis. Deposited eggs may appear as small raised spots on the leaf. Within 10 days hatching larvae tunnel through the mid-leaf tissue, feeding as they go and leaving tell-tale wavy lines that are visible on the surface. Larvae mature in 2-3 weeks, and when ready to pupate, leave the leaf and drop to the soil. Once on the ground, they dig 1-2 inches into the soil and pupate. Adults emerge within 15 days as adult flies. (snippet copied from PlanetNatural)

(The snippets below are taken from Better Homes & Gardens)
Identifying the Pest

Leafminer larvae are tiny, and somewhat flattened to fit inside a leaf. As the larvae feed, they eat the green tissue inside the leaf, leaving a thin, winding trail covered by a papery sheath. The trail may contain small brownish black pellets of insect excrement, and if you look closely you may be able to see larvae. When numerous larvae are feeding in a single leaf, their tunnels may merge, creating large blotches.

Leafminer Control

Because they're protected inside the leaf for most of their lives, it's difficult to control leafminers with insecticidal sprays. However, damage caused by the pest is seldom severe enough to justify spraying except to make the plant look better. For ornamental plants, you can spray a systemic insecticide such as acephate to kill tunneling larvae. Carbaryl, neem, or pyrethrin is effective if sprayed just as the larvae are hatching. If you see large, merged tunnels, the larvae may have already completed their life cycles, making insecticidal sprays pointless.

Control is more important for leafy vegetable crops because feeding by the leafminers damages the edible portion of the plant. Protect vegetables from egg-laying adults by covering the plants with a floating row cover. Secure the edges of the row cover to the ground so that no adults can enter. Remove and destroy affected leaves.

Host Plants

Leafminers may attack many ornamental plants. Some of the preferred hosts are:

Arborvitae
Aspen
Azalea
Birch
Bougainvillea
Boxwood
Butterfly weed
Chrysanthemum
Columbine
Cottonwood
Delphinium 
Elm
Holly
Impatiens
Juniper
Lantana
Lilac
Locust
Magnolia
Oak
Pine
Verbena
Water lily

Commonly affected food crops are Apple

Beets
Citrus
Garlic
Onion
Spinach
Swiss chard
Tomato