Thanks to Pixdaus.com for the above photo, which i found the loveliest, young trees already in full bloom.
The golden shower (Casia fistula) tree is a beautiful sight during summer here in the Philippines simultaneous with Delonix regia, and banaba (Lagerstromoea speciosa). But it is said to be an introduced species from Southern Asia. It is famous also in India, Thailand, Pakistan. As the name implies, its spikes with numerous small flowers droop forming multitudes of dangling golden beauties. Sometimes the whole tree is fully crowned in yellow without leaves, just like the cherry blossoms and Wisteria in temperate countries in spring. Butterflies, bees, birds and other insects love to frolic in its flowers. When fully exposed in a landscape this tree is an awesome accent.
I planted two trees in our property in the province, expecting the awesome view in summers, just like the photo above. I saw young trees which are already full of flowers in some areas in the country. However, it seems our property's soil is too fertile for this plant. It is a legume so it can assimilate nitrogen from the air and use it for its nutrition. Nitrogen is known to produce vegetative growth, so ours become too vegetative and too big. We have to prune most of the very tall branches, the disadvantage of which is the limited mature branches to produce the flowers. We just leave some branches to mature and content ourselves with some few dangling yellows.
Top left shows the tall branches in summer, which we opt to lessen by pruning. Above right shows the typical golden blossoms
Against the blue sky, the flowers are so pretty. Do you notice the black bumble bee approaching the blossoms at the right! It suddenly came when i clicked.
A lot of caterpillars feast on this tree immediately when the new leaves emerge after the first rain. It is good that our tree is very big that there are enough leaves left. Sometimes a big branch lost all leaves to these green larvae with maximum length of 3 inches. They are not cute, but they arrange themselves in a nice fashion.
Can you see the single egg dangling underside a leaf?
And here is the pupa under a Tunera subulata leaf. I've looked for pupa on the tree itself, but cannot find any. It is typical for most larvae to leave the host plants when they are about to pupate. That is a defense mechanism for them.
I hope you can see the butterfly at the center of the photo. I spent much time following these butterflies. Come egg laying time, and it is a wonderful sight looking at the yellows and yellow-green butterflies literally swarming around the Casia tree. I am not sure if they are called sulfur butterflies, but they flutter their wings so fast and fly on an up-down-up-down manner, which is the courting/mating ritual. They also alight so quickly on the leaves, not leaving a few moment for me to take their photos. They also stay up there higher than other butterflies. Unlike the swallowtails, they are more difficult to document.
Above is another version of its color, however the differences in color might just be the gender. I've read that these sulfur butterflies are whites, yellows, and orange. Ours are actually yellows and yellow-greens. The latter are even larger than the yellows. I hope i can take nicer and closer photos this coming rainy season.