These are open bud hickories, and the open bud hickories seem to cross pollenize freely with the walnuts back and forth, while the scale bud hickories do not accept pollen readily from the walnuts.
In the crosses I made, using pecans, pollen was received from the South and put upon the others.
Defn: A plant or vegetable produced by impregnating the pistil of one species with the pollen or fecundating dust of another; -- called also hybrid.
Cross fertilization, fertilization by pollenfrom some other blossom.
Pollen sac, a compartment of an anther containing pollen, -- usually there are four in each anther.
All the Spermatophyta are heterosporous; fertilization of the egg cell is either through a pollen tube emitted by the microspore or (in a few gymnosperms) by spermatozoids.
Defn: Direct fertilization in plants, as when the pollen fertilizing the ovules comes from the stamens of the same blossom; -- opposed to heterogamy.
Defn: To render fruitful or prolific; to impregnate; as, in flowers the pollen fecundates the ovum through the stigma.
It has been attributed to the effluvium from hay, and to the pollen of certain plants.
Defn: A thin membrane existing in the pollen grains of some plants, and situated between the extine and the intine, as in .
Defn: A substance found in the pollen of certain plants.
Pollen tube, a slender tube which issues from the pollen grain on its contact with the stigma, which it penetrates, thus conveying, it is supposed, the fecundating matter of the grain to the ovule.
Defn: One of the fine granules contained in the protoplasm of a pollen grain.
Defn: The male organ of flowers for secreting and furnishing the pollen or fecundating dust.
Defn: A thick mass or collection of hairs on the legs of bees, by aid of which they carry the collected pollen to the hive or nest; -- usually in the plural.
A small portion of certain anthers, which opens like a trapdoor to allow the pollen to escape, as in the barberry.
Bees will carry oatmeal instead ofpollen if the former be put in their way, and birds may be credited with equal adaptability.
It looks, indeed, as if the bird had shaken it from its own feathers, for its intimate actions are too quick and small to be followed, and the pollen is all around it.
The hairs of many bees are feathered for a similar reason, they gather pollen and the pollen adheres to these “feathers” much more readily and in much greater quantity, than it would to simple, unbranched hairs.
This artificial honey contains no pollen grains, in fact any honey found to be free of pollen should be looked upon with suspicion.
The pollen grains are taken to the stigmas in many ways, but the most usual agencies are insects and wind.
The germination of pollen grains is easily observed under the microscope, by putting a few of the grains in an exceedingly weak solution of sugar and water.
Other pollen grains worthy of examination, are those of various lilies, of Eschscholtzia and of Scotch Fir; the last named have curious little air-bladders, for the purpose of rendering them more buoyant.
An interesting collection could be made of various pollen grains, which are easily obtained by merely dusting the anthers of flowers on to a clean, dry slide.
Many lowly plants thrive in weak sugar solutions, after the manner of pollen grains.
Hildebrand fertilised twenty-eight flowers of both forms, each by pollen of the other form, and obtained the full number of capsules containing on an average 42.
Lastly, five flowers were fertilised with pollen from a fourth plant growing at a distance, and all five produced capsules.
This self-impotence does not depend on the pollen or ovules being in an unfit state for fertilisation, for both have been found effective in union with other plants of the same or of a distinct species.
On the other hand, when the pollen of a distinct plant of the Oncidium flexuosum and of the Epidendrum zebra (nov.
Another curious article of vegetable food was the punga-punga, the yellow pollen of the raupo flowers.
They began to come close around me; two bumblebees hung on a frond of goldenrod so close to my face that I could see the pollendust on their fur.
Pussy-willows, their sleek silver paws bursting into fat, caterpillary things, covered us with yellow pollen powder as we brushed past them.
Flowers on the plants of the ninth intercrossed generation were fertilised with pollen taken from a fresh stock, and seedlings thus raised.
Flowers on a completely self-impotent plant of Passiflora alata fertilised with pollen from its own self-impotent seedlings were quite fertile.
I have also given reasons for believing that the inefficiency of a plant's own pollen is in most cases an incidental result, or has not been specially acquired for the sake of preventing self-fertilisation.
Ogle also remarks, smear with pollen the whole back and sides of an entering humble-bee in a useless manner; but the anthers twist round and place themselves longitudinally before they dehisce.
Twelve flowers on the same plants of the third self-fertilised generation, in Table 4/46, were crossed with pollen from the crossed plants in the same table.
Some plants were raised in the greenhouse, and were crossed with pollen taken from a distinct plant; and a single plant, growing quite separately in a different part of the house, was allowed to fertilise itself spontaneously.
Of twenty-eight capsules produced by the crossed plants fertilised by pollen from a distinct plant, each contained on an average 4.
Seven flowers were crossed with pollen from a distinct plant, and produced seven capsules containing by weight 3.
Eighteen flowers were fertilised with pollen from other flowers on the same plant, and produced no capsules.
But so few seeds are produced by protected plants, that the pollen and stigma of the same flower seem to have little power of mutual interaction.
The pollen bodies in the flower-dust of many flowering plants also often assume the form of facetted spheres.
On the other hand, many hermaphroditic flowers, although they have both sorts of sex-organs, are incapable of fertilizing themselves and have to receive this from insect visitors which carry the pollen from one flower to another.
Great masses of lungwort (pulmonaria) being out in flower in April and May, all kinds of insects are then to be found upon it, seeking honey or pollen among the blossoms.
She then goes off to the flowers and labours diligently until she has made up a little ball ofpollen and honey; one of these balls she puts in each cell and lays an egg in it, out of which a tiny grub will be hatched in due time.
They seem able to manage with very little rest, for after all this night-work they are equally diligent in the daytime collecting pollen in which they lay their eggs at the bottom of the tunnels.
The collecting brush of the middle leg is now thrust in between the tarsus and coxa of the foreleg and wipes off some of the pollen from the foreleg brush.
It appears probable that the bee removes the pollen from the head, breast, and abdomen by means of the hairy brushes which are located upon the medial sides of the tarsal segments of all of the legs, being most pronounced upon the hind legs.
Then the middle-leg brushes remove this honey-moistened pollen from the forelegs and they also collect pollen from the breast and the sides of the thorax.
Nearly all of this pollen is collected by the pollen combs of the hind legs, and is transferred from the combs to the pollen baskets or corbiculae in a manner to be described later.
This selected cell may already contain some pollen or it may be empty.
When in the act of loading pollen from the plantar brushes to the corbiculae the two hind legs hang beneath the abdomen with the tibio-femoral joints well drawn up toward the body.
If the combs of a colony are examined, stored pollen will be found in various parts of the hive.
In accomplishing this, the legs cross and it is the tarsus of the right leg which pushes the pollenacross the pincher of the left, and reciprocally.
These scratches are also transverse in direction and they show that the mass has been increased by additions of pollen pushed up from below.
On the other hand, it does not appear at all necessary to mix much drypollen with the wet, nor do the brushes become sufficiently "sticky" from the presence of an abundance of the moistening fluid to endanger their normal functional activity.
These are extremely sensitive, and when touched, or when pollen has been received by them, they close quite rapidly.
All the pollen in each anther-cell consists of a waxy mass, and the adjacent masses of different anthers are bound together by a gummy, elastic band, suspended upon the rim of the stigma.
A bee arriving at this flower naturally brushes against the stigma, leaving upon it some of the pollen gained from another flower.
The act of carrying pollen to the pistil is called pollination, and carrying pollen from the stamens of one flower to the pistil of another flower is called cross pollination.
In many flowers that have both stamens and pistils or are perfect flowers the stigmas and pollen ripen at different times.
With some varieties of fruit it is found that the pistils cannot be fertilized by pollen of the same variety.
We have learned that certain varieties of plums cannot be fertilized by pollen from the same variety, and to make them fruitful some other variety must be planted among them to produce pollen that will make them fruitful.
Cross pollination=, the pollination of a flower by pollen brought from some other flower.
For example, the pistils of the wild goose plum cannot be fertilized by pollen of wild goose plums even if it comes from other trees than the one bearing the pistils.
But they produce large amounts of pollen which is carried by the wind to the pistils.
As they visit plant after plant, feeding from many flowers, their bodies become more or less covered with pollen as they brush over the stamens.
The botanists tell us that a pistil will not produce seeds unless it is fertilized by pollen from the same kind of flower falling on its stigma.
The botanists also tell us that nature has provided that in most cases the pistils shall be fertilized by the pollen of some other flower than their own, as this produces stronger seeds.
This shows what a great amount of pollen is produced and discharged into the air, and it shows that very few pistils could escape even if they were under cover of a building.
These staminate flowers produce pollen and then die.
In this instance practically every flower in the field was visited and pollinated, although no pollen had previously been transferred.
The bags should be tied over the flower buds in the evening and the pollen transferred early the following day.
Before removing the watch glass from this position lift it sufficiently to cause the stigma of the flower to dip into the pollen contained in the glass.
Replace the bags immediately, as an insect or the wind may at any moment bring to the flower the pollen of another variety.
Before beginning upon another variety the brush used for transferring the pollen should be thoroughly cleaned.
The bags need remain only during the day on which the pollen is transferred and may be replaced by a tag to mark the pod.
Since these flowers are normally produced in this way, it is necessary that a transfer of pollen be made from the staminate to the pistillate flowers throughout the agency of insects or by other artificial means.
Five of its stamens quickly develop, the pollen ripens and the anthers burst.
Nearly all are fragrant, as otherwise it would be difficult in the darkness for them to attract the moths which they mostly desire as pollen bearers.
The honeyed flowers, which look to their visits and to the visits of other sun-loving insects for aid in fertilisation, have, so far as possible, covered their tempting cups to avoid the damping or loss of the precious pollen within.
The standards are bright violet with relief of yellow pollen just below the centre, above which are little stigmatic ledges which brush pollen from entering insects.
The stigma having been fertilised with pollen brought by moths from another flower, the corolla closes as before in the early morning, and never again reopens.
This little moth has a sickle-shaped appendage to its mouth-parts which occurs hi no other Lepidopteron, and which is used for pushing the yellowpollen into the opening of the pistil, thus fertilising the flower.
Those flowers, like the crocus and tulip, which open out to the sky must close up, or the precious pollen would be destroyed.
This pollen, as I told you before, has to do with the making of seeds: and stronger seeds are produced if the pollen comes from another flower.
The dandelion opens out to the sun so that flying insects may visit it and carry pollen from flower to flower.
When it has received, in this way, enough pollen to enable its seeds to form, it closes up completely and remains closed until its seeds are ripened.
This pollen is carried about from flower to flower by the bees.
Flowers like the snowdrop and bluebell, which hang downwards, have no need to close up, for their pollen is under a roof of joined petals.
The flower, however, is fertilised by the wind, which carries the pollen grains from one bunch of blossoms to another.
In the morning and evening, the petals close up to a point--really to prevent the pollen from getting drenched with dew or rain.
But when the sun shines, they open out, and lie well back from the stamens so that insects may be lured to take the pollen from one flower to another.
It appears that this plant has lost the capacity for autogamy; at any rate, if a stigma be pollinated with pollen from the same flower on plants in a garden, no result follows.
The bees are getting pollen from the pussy-willows and soft maples, and the first honey from the arbutus.
The bee is abroad in the air, finding her first honey in the flower by your side and her first pollen in the pussy-willows by the watercourses below you.
The product of a single tree, ripening its pollenat the right time of year, would be sufficient for the wants of a whole hive.
Oil shale is a fine-grained sedimentary rock containing organic matter which was derived chiefly from aquatic organisms, waxy spores and pollen grains .
This ooze was composed of the remains of phytoplankton, blue-green algae, zooplankton, bacteria, and somepollen and spores.
Munson, Denison, Texas, raised Carman from seed of a wild post-oak grape taken from the woods, pollinated with mixed pollen of Triumph and Herbemont.
Caywood, Marlboro, New York, grew Poughkeepsie from seed of Iona fertilized by mixed pollen of Delaware and Walter.
There is, of course, some danger when the buds are well developed that the pollen may be squeezed out and so reach the stigma or adhere to the instrument and thus contaminate future crosses.
It is, by the way, best to delay emasculation until just before the flowers open, but one must be certain that the anthers have not discharged their pollen before the flower has been emasculated.
This first operation having been performed, the cluster of grape-flowers must be tied securely in a bag to protect it from foreign pollen which otherwise would surely be carried to the stigma by insects.
A brush is very wasteful of pollen and often becomes a source of contamination to future crosses, so that the scalpel is the better implement of the two.
The flower from which the pollen is to be taken must be protected from wind and insects; otherwise pollen from another flower may be left on it.
The work of pollination is best performed in bright, sunny weather when the pollen is very dry.
As soon as the stigma is ready to receive the pollen, the bag is removed and pollen from the male parent is applied, after which the bag is again put on the flower to remain until the grapes are well set.
Examined with a microscope, it is found that self-sterile plants usually bear abortivepollen and that the percentage of abortive pollen grains varies greatly in different varieties.
In a greater number of cases the pollen is found defective.
There are various ways of obtaining pollen from ripe anthers and applying it to the stigma of the flowers to be crossed.
The upright or depressed stamen does not always indicate the condition of the pollen, since there are many instances in which upright stamens bear impotent pollen and occasionally the depressed stamens bear perfect pollen.
