Night of the Queen 2020

The COVid19 numbers are sky-rocketing, the timeline indicating that the Memorial Day and Mothers Day weekends with dropped lock-down have more to do with it than the protest marches, but they will also soon show consequences. AZ hospitals at capacity, Better not get sick here now.  I am dreading my gallery duty on the 11th of June.

Photo by Shawna Caldwell: How the fire in the catalinas started

Not to forget that other, probably greater problems loom: Global Warming is pushed out of the news, The slowed-down world economy may provide a small reprieve.   But our weather patterns are ominously confusing.  We had monsoon like thunderstorms for several afternoons, nearly a month too early.

Push Ridge fire by Bill George

Result: fires. We can see them glowing at night and the smoke now. The second photo was taken by a friend who lives in a development that was carved into the mountains about 15 to 20 years ago, so I remember open desert there. 

But some eternal (?) natural rhythms are still operating: last night was the night of the Queen.  Once a year a twig-thin cactus (Peniocereus greggii) produces the most beautiful, fragrant flowers. The Mystery: within miles, they all open at once. I have not been able to relate it to moon phase, temperature, day length (the date can vary by a month) or precipitation (usually there is none before the cacti bloom) barometric pressure - nothing I can measure seems to provide the trigger, and yet, they are completely synchronized. Usually, Tohono Chul Park close to Tucson monitors and celebrates the bloom, so people are aware of the event. This year the park is closed. This morning, I found several on our dog walk. We live right in the middle of a big population. This year there were fewer flowers than usual. 

Honey Bees were all over the flowers in the morning sun. These opportunistic generalists among bees are probably not suited to pollinate the big flowers. That is probably usually done by big Manduca and other Sphinx Moths. But those have been out in numbers a couple of weeks ago. I saw them at my black lights.   At the moment they seem rather scarce.  Perhaps I just do not see them at my lights because the moon is rather full..

Peniocereus greggii, Queen of the Night

By the 12th of June the Big Horn Fire in the Catalinas had spread. The inferno came down the mountain towards foothills homes and 100s of people had to evacuate, others are on stand-by.

View towards the Catalinas from Tucson on June 11th 2020

The Arizona Queen of the Night, Peniocereus greggii

Two of my watercolors of the Night-blooming Cereus

Last night the Arizona Queen of the Night (Peniocereus greggii) bloomed in our part of the desert. Buds on all plants in our area simultaneously opened at sunset, the petals still growing and stretching outward for hours, until finally the dense anthers and star-fish-shaped stigma were presented above a skirt of slightly drooping petals.

I don't know what signal synchronizes this magical event. It's not day length, because it can occur any time between mid June and the beginning of August, and Tohono Chul Park 30 miles to the east celebrated the bloom about a week ago. The blooming is also rather independent of the onset of the rainy season, probably because the plants are drawing on the resources of a large underground bulb, although the hydration state of a plant seems to decide whether it's going to bloom in any given year at all. Sometimes, often following a very rich flowering, all the visible parts of a plant just dry off and crumble, and it takes years until the next flowers appear.

 The vegetative parts of this cactus are so thin and unassuming that they blend in completely with the branches of the Creosote bush. Our friends Frank and Lynn bought the land next to us years ago and were very much looking forward to the flowers of one Queen that we had planted, but we were all surprised by several other large plants that suddenly opened their flowers last night. 

The cactus flowers stay open into the early morning hours, so a couple of hours before sunrise Cody and I went out into the desert to find some more blooming Arizona Queens. At night usually a cloud of sweet fragrance is the first sign that leads pollinators and photographers to the plants. But at dawn, the pale flowers stand out like beacons. 

The flowers are about the size of a baseball. Many plants are not more than knee-high, but today I found several that were taller than I. This is impressive considering that a heard of cattle had a devastating 4 year run in this 400 acre parcel of state trust land. Wile the bovines destroyed Paloverdes, Prickly Pears and Ironwood trees,  they left the fragile stems of E. gregii untouched in their cover of Creosote branches.

This ten-flower cactus was the prize of the morning. I wished you could smell the cloud of sweet fragrance that surrounded it. This smell attracts the nocturnal sphingid moths that are the main pollinators of P. greggii. Big Manducas and the White-lined sphinx Hyles lineata are usually very common, but this year I have only seen a few at my black lights. 

When the moths are scarce unpollinated flowers probably stay fresh longer and their the beacon-like appearance at day break may insure visits by bees, although those promiscuous pollen gatherers are probably not the most reliable pollinators.