Excerpts from Jim Conrad's
Naturalist Newsletter

Orange Jasmine, Mock Orange or Chinese Box -- MURRAYA PANICULATA

from the January 31, 2010 Newsletter issued from Hacienda Chichen Resort beside Chichén Itzá Ruins, central Yucatán, MÉXICO; limestone bedrock, elevation ~39m (~128ft), ~N18.52°, ~W95.15°
ORANGE JASMINE FRUITING

Next to the church there's a handsome little tree with a compact, dark-green crown and smallish, evergreen, pinnately compound leaves. It's fruiting now, as shown above. The fruits remind me of smallish, inch-long jalapeño peppers, but when you break one open you only find a couple of seeds, while a pepper has many, plus the tree's bruised fruit has a sharp, citrus odor very unlike any pepper.

The evergreen, pinnately compound leaves along with the citrus odor of the fruits reminded me of eastern North America's Prickly-Ash, genus Zanthoxylum, in the Citrus Family, the Rutaceae. However, Prickly-Ashes are plenteously and painfully prickly, but I couldn't find a single prickle on this tree. Also, Prickly-Ashes produce very different fruits. Checking to see if the church-tree might still be a member of the Citrus Family I plucked a leaflet, held it up against the sun, and saw strong evidence that it WAS, as shown below:

pellucid dots in member of Rutaceae, Orange Jasmine, Mock Orange or Chinese Box -- MURRAYA PANICULATA

We've seen before how leaves of members of the Citrus Family often contain "pellucid dots" -- glands filled with aromatic oils, and which glow brightly when held against the sun. So, my first thought was that here was a genus of the Citrus Family with which I'd not yet made acquaintance, and I could hardly wait to bring out my books and figure out who it was. Before heading to the books I was careful to note that the tree was much-branched from near its base and its bark was blotchy, almost like eucalyptus bark. You can see its trunk next to some Mother-in-law Tongues below:

Orange Jasmine, Mock Orange or Chinese Box -- MURRAYA PANICULATA

The little church tree turned out to be a native of South and Southeast Asia, China and Australasia, but, according to the Web, much planted in the southern US. Somehow I must have missed it. It goes by several English names, including Orange Jasmine, Mock Orange and Chinese Box. It's MURRAYA PANICULATA, and it is indeed a member of the Citrus Family. The flowers are especially fragrant. As an ornamental it makes a fine tall, dense hedge, flowering and fruiting throughout the year as it attracts many bees and birds. However, it's vulnerable to several diseases, and is the main host of the insect vector of the Citrus Greening Disease.


from the August 23, 2015 Newsletter issued from Yaxunah, 20kms southwest of Chichén Itzá; elevation about 300m (100ft), N20.538°, W88.678°, Yucatán, MÉXICO
ORANGE-JESSAMINE FLOWERING

Back at Hacienda Chichen in 2010 we looked at the Orange-Jessamine, Murraya paniculata, growing next to the old church there. I halfway watched that tree for over two years, hoping to see it flowering, but I never did. One reason I always missed the flowers is that they develop, open and fall away during a short period, about a week.

However, last week in Yaxunah I happened to be visiting a friend's hut when I noticed panicles of flower buds forming on the resident Orange-Jessamine, so, hoping to see the flowers,  I began checking for them every day. Soon the first blossoms appeared, but I resolved to wait until the tree was in full bloom for pictures.

This week at the peak of the tree's flowering, when it was loaded with spectacular clusters of thumbnail-size, white, star-shaped blossoms that drenched the area with a very sweet, fairly intoxicating fragrance, an afternoon storm knocked two big trees onto the hut, covering the Orange-Jessamine before I got my pictures. When finally the mess was cleared away, only two or three blossoms remained on the mostly undamaged tree. The last remaining flower of a small panicle is shown below:

Orange Jasmine, MURRAYA PANICULATA, flowers & leaf

The flower has reason to look like a citrus flower because Orange-Jessamine is a member of the Citrus Family, the Rutaceae. However, the blades occupying the right half of the above picture are not leaves alternately arranged on a stem, as would be the case with an Orange, Lemon or Grapefruit tree, but rather are leaflets arising from the rachis of a pinnately compound leaf. This is a good field mark for the species, as are the facts that the tree is spineless, its leaflets are blunt-tipped, not sharply so, and that the leaves' rachises aren't "winged." A close-up of the flower is shown below:

Orange Jasmine, MURRAYA PANICULATA, flower

The most eye-catching feature of the blossom may be its sturdy style arising from the flower's center, topped by an egg-shaped, yellowish, granular-surfaced stigma. However, such stout styles are common in the Citrus Family.

Orange-Jessamine is originally from India but now is planted throughout tropical America, and sometimes escapes.