Another example of the gradual effect of habit on plants my uncle learned from the late Dr. Walker. The Brazilian passion-tree is, you know, an evergreen in its native country; but when the Doctor was a boy in 1773, some plants of it near Edinburgh annually lost their leaves. During his life, however, they became gradually enured to the climate; and he says that in his latter years, in sheltered situations, they have retained their foliage through the whole winter.
I asked my uncle whether those plants, which have come from a warmer region, and are naturalised here, flower later in this climate than in their own.
“The times of the appearance of vegetables in the spring seem,” said he, “to be influenced by early acquired habits, as well as by sensibility to heat. That same Dr. Walker, whom I mentioned a few minutes ago, had some very singular ideas on this subject: his opinion was, that plants removed from one climate to another, generally observe their original season of flowering, unless prevented by some powerful cause. The climate of Spain and Portugal in December and January suits the flowering of the laurestinus; and you have seen that the cold of Gloucestershire in those months was not sufficient to deter it from following its old habits. In the northern parts of Scotland, however, it does not flower till April. Dr. Walker thought the flowering of any shrub in winter in this climate was an indubitable proof of its not being a native; and he therefore supposes the arbutus to have been a native of Iceland: in the fact, I believe, he is right; but, when the similarity of the climates is considered, it is rather a whimsical proof of his doctrine.
“He gives, however, several instances of plants brought from the southern hemisphere, which flower there at the time that the sun is in the tropic of Capricorn, and which adhere in this country to their old December rule, without obeying the influence of the sun when in Cancer.”
I afterwards met my uncle in the garden, where he showed me an immense quantity of buds on the peach trees, and took great pains in teaching me the difference between the flower buds and leaf buds—the former short, thick, broad and full, with a downy covering;—the leaf buds much less downy, longer, and not so thick. In a few weeks, he says, I am to see these trees in full flower, notwithstanding this wintery weather.
7th.—From all I had heard Colonel Travers say about rice, I imagined that its cultivation was almost confined to India; and I had no idea till yesterday that it grew in North America, and even in Germany. I renewed therefore the conversation to-day, and I now find that it is so much cultivated in Spain, particularly in the low parts of the province of Valencia, that a very large quantity is exported every year.
The ground is prepared for it there by first sowing beans; and when they come into blossom, which is about March, they are ploughed in for manure, and flooded with water to the depth of four inches. After a third ploughing the rice is sown; and when it comes up, it is transplanted to another prepared field, and again covered with water. Each stem produces about twenty-four fold. When ripe it is gathered in sheaves, and put into a mill, the lower grinding-stone of which is covered with cork, by which means the chaff is separated without bruising the grain.
My aunt tells me that rice grows wild in the swamps of Upper Canada; and that the shallow parts of Rice Lake, which is near the residence of Mrs. * * *, is full of it. Her letters describe it as having the appearance of reeds with long narrow leaves, and bearing clusters of flowers at the top of the stem.
It is curious that the plant chiefly cultivated in the Sandwich Islands for food is managed very like rice;—the taro, to grow in perfection, requiring irrigation. The fields are divided for that purpose, like the rice grounds of the East, into small squares which may be easily flooded, and the roots are planted in rows. The root of the taro when roasted resembles the yam; but it is usually pounded into a paste, and then mixed with water, so as to become of the consistence of porridge.
The Sandwich Islands are nearer to you than to England, and yet perhaps you do not know, dear mamma, that although the bread-fruit is the most important of all their vegetables, they have another very useful one, called Tee by the natives. The root is sweet, and produces a pleasant liquor, but a little intoxicating. The leaves woven together form a light cloak for the inhabitants of the mountains;—something like those formed of the palm leaves by the poorer natives of Hindostan, to shelter them while at work in the open fields. Fences are often formed by planting the tee roots close together; but what makes the plant particularly remarkable is, that a stalk of it is with them the symbol of peace, as a branch of olive is with us.