April 1983 may bring to the nation's capital a spring magnificence unknown in many a year. It's cherry blossom time, of course, the month when Washington desperately tries to coordinate parades and pedal-boat races to coincide with the elusive glories of more than 3,000 trees donated by Japan to the United States early in this century.
This year it seems that the whole process of budding and blooming is proceeding at just the right pace to bring Washington its blossoms by April 1 - just two days before the opening of the National Cherry Blossom Festival (April 3-10).
No one can say for sure what will happen in the way of Washington weather between now and then: For instance, a spell of warm weather, causing the blossoms to unseal, followed by a cold snap would make them turn brown. All that the experts, including William H. Anderson, chief scientist for the national capital region of the National Park Service, can say at this point is that this year the trees - which often bloom only in batches - should bloom all at once, providing a truly glorious spectacle.
The focus of all this attention, 3,500 Yoshino variety cherry trees, arrived in this country in 1912, a gift from the city of Tokyo for the swampy area newly transformed into Potomac Park by the US Army Corps of Engineers. Today, 25 percent of the original plantings - single white-flowered cultivars as the botanists put it - adorn the Tidal Basin area. In January 1981 the United States offered a gesture of thanks to Japan by presenting with appropriate pomp and circumstance 2,000 cuttings of Yoshino trees as replacements for pollution-damaged trees along the Arakawa River outside Tokyo.
The Yoshino cherry trees aren't Washington's only cherry trees. Close to the Washington Monument in the Sylvan Theater area, one can find 200 Akebono cherry trees with delicate pink petals, while nearby Haines Point, a favorite Washington spot for picnicking and miniature golf, boasts double-flowered Kwanzan cherry trees. Behind the Jefferson Memorial, check out the weeping cherries with their pendulous pink blossoms, and consider yourself well on the way to a minor education in Prunus Yedoensis, Prunus Subhirtella, etc.
Though the cherry blossoms surely represent the ephemeral at its most glorious, they are indeed short lived. Therefore, you might as well sample a few other of Washington's many attractions while you're there.
If the weather remains splendid (and even if not), by all means head for the National Zoo, now conveniently reached by the Metro subway. Take the Red Line to the Woodley Park-Zoo station. Though a drizzly day might complicate your ambling among the zebras and camels, there's nothing to prevent your diving indoors for a leisurely afternoon among snakes and crocodiles in the Reptile and Amphibian House and its bonus facility called the HERPlab.
Herpetology is the study - you guessed it - of reptiles and amphibians. In the HERPlab, opened last fall, zoo visitors from age six on up may absorb a number of zoological concepts through games, manipulation of materials in activity boxes, and observation of live animals such as a corn snake, an African bullfrog, and anolis lizards.
Judy White, catalyst behind HERPlab's formation and chief of the zoo's education office, explained that HERPlab's goal is to introduce children and adults to the anatomy, behavior, communication, character, and classification of reptiles and amphibians. One can discover how snakes hear, when lizards change color, how the skeleton of a gaboon viper differs from an alligator snapping turtle, which species are at risk and what can be done to lessen the risk - and what we're doing to make things worse.
April 1 shapes up as a red-letter day at the zoo as well as along the Tidal Basin with its blossoming cherry trees.
April 1 also is retirement day for Theodore H. Reed DVM, who joined the National Zoo staff in 1955 and has been zoo director since 1958. Two events that day honoring Dr. Reed's tenure with the zoo will be the reopening of the renovated Small Mammal House and the introduction of Monkey Island, the new outdoor home for a half dozen Barbary macaques.
Opening day will find some facilities still in the works, but two multispecies exhibit areas are planned for rapid completion. Mouse deer, tree kangaroos, and tree shrews will be among those animals sharing space in the Austral-Asian section while sloths, hairy armadillos, and acouchis (South American rodents) will live next door in a habitat built for them.
Not far from the National Zoo, which is part of the Smithsonian Institution but a considerable distance away from the main conglomerate on the Mall, is an unusual addition to Washington's museum scene: Hillwood Museum. Hillwood was the last permanent residence of General Foods heiress Marjorie Merriweather Post and is now operated as a museum by the Marjorie Merriweather Post Foundation.
If Hillwood merely represented the accumulated possessions of a very rich woman, a visit might hardly be justified. What will, with reason, draw you to Hillwood are the brilliant collections of Russian porcelain, glass, silver, and religious objects that together rank Hillwood as one of the richest repositories for these items outside Russia.
In the Russian Porcelain Room you'll find items ordered from the Imperial porcelain factory by Tsarina Elizabeth I, who reigned from 1741 to 1761, for use in the Winter Palace. The four services used by Catherine the Great during her annual dinners for knights of the Imperial Orders are also here, along with goblets made for the 300th anniversary of Romanov rule in 1913.
In the Icon Room, one may admire 17th-century silver chalices, a miniature iconostasism (a multipartitioned screen bearing icons and perhaps used on military expeditions), and the pink Russian imperial Easter egg artist-craftsman Faberge made for Tsar Nicholas II to present to his mother in 1914. Though there are many other items by Faberge - a second imperial Easter egg, miniature frames , bell pushes, a snuff box, seals - the staff feels that the porcelain and glass collections are represented in greater depth at Hillwood.
The foundation of the collection was laid by Joseph E. Davies, whom Marjorie married in 1935 and accompanied to Moscow in 1936 when he became the American ambassador. It was Davies - a political appointee whose selection dismayed embassy professionals and whose Moscow tenure earned the Davieses the appellation ''Babbitt Bolsheviks'' - who first became obsessed with Russian art and made a point of collecting as much as possible.
The year 1937 marked the height of the ''great purge'' in Russia, and the Russian ''commission shop'' was what writer Robert C. Williams in ''Russian Art and American Money'' described as a ''marvelous rummage sale or pawn shop'' for Westerners like the Davieses. In these shops Russian citizens ''disposed of items which, if retained, could bring jail or death.'' Apparently religious objects and ''bourgeois trinkets'' were equally dangerous.
The exit of the Davieses from Moscow coincided with the end of the Soviet government's 10 years of selling art objects, often secretly, to the West. Many of these ojects were part of the Romanov treasure.
Though a visit to the house must be by appointment and with a guide, once on the grounds you may wander about freely - to the Greenhouse, the Russian dacha or country house, the Japanese garden, or the lawn with its views that stretch to include the tip of the Washington Monument.
The Smithsonian Museum on the Mall and the National Gallery of Art are Washington's blockbuster attractions, of course, and fortunately they can rarely be thought of as ''old hat.''
The National Gallery of Art has been very much in the business of making news for several years now with the opening of the extraordinary East Building and the resulting lower level renovations, creating a bright, fresh environment as delightful for relaxing as for studying the Art of the Ages.
On Feb. 3, the National Gallery officially opened a new ''museum within a museum'' on the completely remodeled ground floor of the West Building. In the exhibition areas, the work of famed photographer Alfred Stieglitz is on display until May 8. There are 170 photographs - part of a huge collection donated by his widow, painter Georgia O'Keeffe. Another temporary exhibition includes 100 drawings from the Holy Roman Empire - works from central European artists between 1540 and 1680.
Before you've exhausted your capacity to absorb works of art, step into the Central Gallery for a tour of what are known as ''American Naive Paintings'' - compelling direct portraits and landscapes painted by artists of the 18th and 19 th centuries who never stepped near formal or academic training of any sort. The National Gallery exhibit has been selected from over 300 ''naive'' works given to the museum by Edgar William and Bernice Chrysler Garbisch. You'll find that perspective and proportion are awry by our hard-nosed photographic standards, and yet the simplicity and power of many of the works is dramatic and fresh.
All of these artistic marvels will await you in Washington - if only you can muster the strength to move from the sight of that masterpiece by Mother Nature herself - those sweet, delicate blossoms on Washington cherry trees.
If ever there were a spring to venture to the nation's capital this is truly the one. Practical details:
National Cherry Blossom Festival: for information call (202) 347-2221 and this number lists events of the week. Cherry Blossom Festival Parade, Saturday, April 9 at 12:30 p.m. Location: Constitution Avenue between 7th and 17th Streets NW. Note: Grandstand seating available through Ticketron at $9.25 per person. Also available in grandstand area on day of parade.
Hillwood museum: 4155 Linnean Avenue NW, Washington, D.C. 20008. Telephone: ( 202) 686-5807. Tours: Monday, Wednesday, Thursday, Friday, and Saturday at 9 a.m., 10:30, 12 noon and 1:30 p.m. Admission $7. Minimum age: 12 years. Admission to gardens only: 11 a.m. to 4 p.m., ticket $2. Note: reservations only.
National Zoological Park: Open every day except Christmas. Hours: April 1 to Oct. 15, grounds open 8 a.m. to 8 p.m., buildings open 10 a.m. to 6 p.m. From Oct. 16 to March 31, grounds open 8 a.m. to 6 p.m., buildings open 10 a.m. to 4: 30 p.m. HERPlab: open Wednesday to Sunday 12 to 3 p.m. In busy season get tickets at door to HERPlab.
National Gallery of Art. Hours: 10 a.m. to 5 p.m. Monday through Saturday. Sunday: 12 noon to 9 p.m.