THE ROSY CHALICES that you have noticed all over Washington the past few days are Magnolia soulangeana, and it would not have occured to me to mention them except for an astounding number of inquiries what they are. Sometimes people call them "tulip tree," which I dislike for the sound reason I never called them that myself, and it is in herently dumb, as if one were to call a tulip a "magnolia flower".

The pink magnolia is hybrid, not a wild species. Its parents are the awesomely beautiful wild M. denudata , the Yulan of China, and M. lilifora, a somewhat pallid lavender magonlia, also Chinese.

I do not see either of these in gardens. The Yulan, which may be the most beautiful of all magnolias, is white with a strong sweet lemon fragrance. It is far more beautiful than its pink offspring, and the pink progeny have no scent worth mentioning.

It is almost impossible to find the Yulan at nurseries, but that has nothing to do with the fact that it is supremely fine.

M. lilifora also appears to be missing from common cultivation, and I do not miss it. The ones I used to see were all rather washed out in color.

One that you do see often is a dark form of m. lilifora, called M.i. nigra . It is not black, but dark reddish purple. It makes a smaller tree, a shrub usually, and it blooms late enough to escape the spring freezes that often blacken the flower of the others.

While we're about it, there are two other magnolias that, like all these, bloom in early spring before the leaves appear.

The most beautiful of them is M. stellata , the star magnolia, which makes a rounded shrub or small tree up to 18 feet or so, but often much less.

Its blooms have 20 little white or blushcolored straps radiating from a center, and they look as much like stars as necessary, no doubt. They are softly and sweetly scented and sometimes on mild damp days you can smell the flowers 50 feet away. Possibly the finest scent of all magnolias.

And needless to say, this is the greatest magnolia of all for small gardens. Apart from the white form, there is one that is a little deeper than blush pink, and a nother that is about as deep a pink as the 'Radiance' rose. Neither of the pink forms is readily obtainable so far as I know.

It seems to me that in recent years a number of trees of the early white-flowered M. kobas have been sawed down or otherwise disappeared from Washington's parks. This tree is not as showy as the others mentioned. It has rather gray pleasant bark and the flowers are rather small. Still, a large tree in bloom is a fine sight. Most gardeners would not be much interested in it unless they had plenty of woodland, in which odds and ends of trees could be grown for the hell of it.

Our two American magnolias, the best-known ones, are the sweet bya, M. virginianan, with neat waxy white-cream flowers once the spring really warms up.

they are the size of large walnuts or small tangerines, depending, and the aromatic leaves are perhaps six or eight inches long, maybe no more than four inches (again, depending) and they are half-evergreen. That is, some of them hang on in winter but up here most fall off. They are splendidly fragrant.

The great magnolia of the Suth is M. grandiflora , the bull bay, with flowers 10 inches or a foot in diameter, of flawless wax-suede substance and texture, powerfully scented, and the glossy heavy leaves are up to a foot long.

This, which is the tree usuallly meant when one says "magnolia" without any qualifying, is a plant that varies a lot in size of leaf and in other ways. Some have bigger blooms than others, some are more likely to rebloom in October than others, some are nicley felted beneath the leaves with a soft russet fuzz, while others are smooth.

All of them are irresistible to starlings, grackles and anything else that flies, and I myself am by no means as fond of them as a Southerner should be.

The leaves dribble down unsteadily throughout the year, but chiefly when you have just swept a lot of them up.

Possibly my prejudice against dank forests has shown up in this space before now, but let me say I cannot think of a more awful tree to have against the house. Nothing grows under it, the shade is too dense, and of course no sun can penetrate its leave if they happen to be near a window. It is marvelous tree, though not showy in flower, at the end of an open sunny garden, and if the place is large enough nothing is quite so glorious as this magnolia with reflections in the water and a certain amount of cut stone and bronze and lead. It is ideal, in other words, for burial grounds.

It is also a grand tree for Blanche Dubois-type folk in run-down New Orleans-type ruins with irregular hours and vague means of income.

And yet some of my best friends plant these magnolia in city gardens. It takes all kinds.

The big-leaf magnolia, M. macrophylla, has light green leaves up to 30 inches or so in length and attractive large fleeting flowers not easily seen unless they are cut. It drops all its leaves in winter, and is a very beautiful tree-the leaves are more often 18 inches than 30, by the way.

The cucumber tree, named for the shape of its green fruit, is also native to American deciduous forests. It makes a beautiful tree, architecturally, and its leaves are conspicuously large and fresh looking, though half the size of M. macrophylla. It is somewhat neglected, doubtless because its flowers are not showy.

There are many other magnolias uncommonly seen. The one most worth dreaming about is maybe M. sargentiana robust , with great soulangeana type flowers, only more elegant, which nod down from the branches. I do not recommend it to the general gardener. Alas.

Maybe I should point out that M. soulangeana includes many named varieties, differing in color, fullness of bloom, time of flowering, and among the most admired of these are 'Alexandrina,' 'Lennei and so on.

The mere fact that the wild Yulan is more beautiful than the pink M. soulangeana does not mean the pink one is not worth growing. It is exceptionally beautiful, and any garden is the richer for it. It is supremely beautiful. But you will notice nurseryman are far more likely to offer the very good rather than the very best. Sometimes that is because they think popular taste is bit vulgar. Sometimes because it is too much trouble to find and stock the Yulan. Sometimes because they simply do not know any better. CAPTION: Pictures 1 And 2, 'Magnolia stellata' (left) and 'M. soulangeana.' Photo by Douglas Chevalier-The Washington Post