January iB, 1893.] 



Garden and Forest. 



35 



for forty consecutive days counted the microbic contents of 

 the air in and outside and found from twenty-three to twenty- 

 eight times more bacteria in the air on neighboring- fields. 



Referring to specific diseases in particular, Dr. Pettenkofer 

 argues, from observations in India, the influence of forests on 

 cliolera and yellow-fever germs. He and otlier investigators 

 find that villages surrounded by forests are free from both 

 diseases, and that the withdrawal of troops into wooded dis- 

 tricts stops the spread of the disease. On the other hand it 

 has been observed that with the removal of the forest, 

 cholera appears. Extensive moors seem to offer similar anti- 

 bacterial soil conditions and immunity from these diseases. 

 Says Dr. Ebermayer : "If it is considered that the comma 

 bacillus which produces cholera makes great demands in its 

 nutrition and belongs to the mostsensitive bacteria, especially 

 sensitive against free acids, being destroyed by the sour 

 stomach juices ; that when dried it dies quickly and is easily 

 destroyed by decay-producing bacteria, prospering best in a 

 temperature of 90 to 100° Fahrenheit, and ceasing to grow 

 when the temperature sinks Vjelow 61° Fahrenheit, the pro- 

 tective influence of forests against this epidemic is easily ex- 

 plained." 



According to Marchiafara and Celli, malaria is no bacterial 

 disease, but is produced by parasitic protozoa, called by these 

 authors "Plasmodia," which are found in the red-blood cor- 

 puscles. Although their exterior existence is unknown, they 

 probably come also from the soil. Warmth and wet soil, 

 periodically dry in the upper strata, are the best conditions 

 for their development. As long as the soil is covered by 

 water, the air being thereby excluded, there is no danger. 

 The danger arises during the change of the water stage, 

 when the soil becomes exposed. Malaria plasmodia do not 

 rise high abov^e the soil, whence the desirabiUty of houses 

 elevated above the danger-line. With water and temper- 

 ature conditions such as exist under forest cover, these 

 Plasmodia have less opportunity for development, and the 

 absence of dust-formation and lack of movement of air pre- 

 vents their distribution, while the vi^ater conditions in the 

 forest soil are not as liable to the sudden changes necessary 

 for their development. 



In conclusion it may be said, in regard to the larger parks in 

 cities, that, besides their most desirable aesthetic influence, 

 their value is mainly in the better drainage conditions of the 

 soil which they secure, and besides the coolness and circula- 

 tion of fresh, pure air, which they induce, in their capacity of 

 absorbing decaying animal matter, in the absence of dust 

 and in the reduction of bacterial life. These effects, to be 

 sure, are confined to their own limits and nearest neighbor- 

 hood, but the possibility of breathing purer air, at least 

 occasionally, must be an advantage to those who are forced 

 to spend their lives in the impure conditions of a large city. 



Washington, D. c. B. E. Fernow. 



Correspondence. 

 The Season in Northern California. 



To the Editor of Garden and Forest : 



Sir, — Northern California has had a very open autumn and 

 early winter. The rainfall early in October was sufficient to 

 start the grass. The later storms were short, but with violent 

 winds and great rainfall. During December or January we 

 expect from ten days to three weeks of frosty weather ; near 

 the ocean and around San Francisco Bay the temperature does 

 not fall more than a few degrees below freezing. Geraniums 

 and Fuchsias become perennial, running wild over houses 

 and even in neglected places. In the valleys north of the Bay 

 and the Sacramento valley it is colder during these frosts, the 

 thermometer falling as low as twelve degrees below freezing, 

 although favored spots are almost frostless ; the earliest fruit, 

 vegetables and oranges from California are grown north of 

 San Francisco. The frosty spell this season lasted two weeks, 

 with clear, bright days and the ground in shady places re- 

 mained frozen all day. Probably twenty-four degrees would 

 mark the lowest point reached. 



In our little town, as elsewhere, the Chrysanthemum is a 

 great favorite, and a church flower-show brought out quite a 

 creditable exhibit. All the plants are grown out-of-doors. We 

 have little advantage over eastern cultivators, for, although we 

 may get a fine bloom without shelter, the light frosts of late 

 October endanger the earlier kinds, while with late varieties 

 we can do nothing out-of-doors. From my collection of more 

 than a hundred varieties I am discarding all late bloomers, 

 and find that I can usually get a fine bloom from early and 

 middle season Chrysanthemums with slight protection. 



From the large number of good Chrysanthemums it is easy 

 to select enough of the earlier sorts for a varied collection. 

 This season I found Lord Alcester, Madame M. Fabri, Mikado, 

 Louis Boehmer and Melanet Robinet among the most satis- 

 factory. I must say, with Mr. J. N. Gerard, that a well-grown 

 plant, with dozens of naturally grown flowers, is a more pleas- 

 ing object than the immense blooms of the artificially trained 

 plants. Here, where we irrigate in summer, the problem is 

 rather to keep plants down than to stimulate growth ; a small 

 plant in May, such as dealers send out by fall, will be a tree 

 six or seven feet high, even when repeatedly pinched in ; and 

 even May slips, in open ground, will become unmanageably 

 large. 



Roses blossomed until late this season. Early in December, 

 when the frosts set in, many sorts were blooming freely, and 

 on Christmas-day I examined buds of Hermosa and found them 

 uninjured, so that a few warm days will bring them out. There 

 is nothing more satisfactory than Roses. I like to try those 

 new to me, although new Roses will not compare with older 

 ones. An old sort, Delphine Grandit, charmed us this fall. It 

 is always a free bloomer, but it is not fully double in the sum- 

 mer ; late in the fall, however, it gave great ivory-white roses, 

 the best we had. Of some 150 sorts which I grow. La France 

 is the best. The most satisfactory kinds during the past sea- 

 son have been La France, Duchesse de Brabant, Bon Silene 

 and Catherine Mermet. There are many others which I 

 esteem highly, but for rehability and real satisfaction at all sea- 

 sons I must commend these four. Among satisfactory and 

 free-blooming climbers are Reine Marie, Henrietta, William 

 Allen Richardson and Gold of Ophir, which is exactly hke 

 Richardson, except in color, which is a copper-red. 



On Thanksgiving-day I noticed Manzanitas in blossom on 

 the mountains, and on Christmas-day they were blooming in 

 town, and the flowers of California Laurel were almost open. 

 The difference in climate in a short distance in California is 

 remarkable. A German of my acquaintance purchased trees 

 of Orange, Lemon, Lime and Loquat three years ago, which 

 he planted a few miles from here on the mountains. They have 

 been unprotected, have never been touched by frost, and 

 Lemons were in blossom in last December. In a similar place 

 I have seen Blackberries in flower, and green and ripe fruit at 

 this season, yet here frost did not go out of shady places for a 

 week. It is for this reason that nadve trees or shrubs blossom 

 in some spots on the mountains a month or two earlier. In 

 the fall and spring the frost often draws a sharp line through 

 hill-side vineyards, freezing all below it. 



A charming object in December is that always beautiful tree, 

 the Madrona. It is a native here, and throughout the town it 

 has been spared in yards. There are scores of healthy young 

 trees, twenty to twenty-flve feet high and erect, with glossy 

 brown bark and large oval evergreen leaves. The berries, 

 which are at first orange, and later turn to crimson, grow in 

 large clusters. This year I have noticed some seven inches 

 long and three inches through. One tree, about three feet 

 through, forty feet high and spreading finely, was such a mass 

 of crimson berries as almost to hide the leaves. This, with 

 California Holly (Photinia arbutifolia), another fine evergreen 

 with bright red berries, are the Christmas decorations. Mis- 

 tletoe abounds, but is not even noticed. 



uidah, Cai. Carl Fiirdy. 



A Case of Inherited Variegation. 

 To the Editor of Garden and Forest : 



Sir, — A stock of Cornus Mas, upon which a variegated form 

 was grafted, was allowed to send up a branch, which eventually 

 equaled in size the variegated portion. During 1890 seeds were 

 borne by each part. The seeds were sown, and the following 

 spring the young plants which came from the seed borne by 

 the variegated portion showed the same coloring as the parent 

 form ; the other seedlings were normal. Another noticeable 

 difference between the two lots was that the variegated seed- 

 lings were much weaker from the start, and eventually Ihey all 

 died, although they were grown under the same conditions as 

 the others, and these are still alive. 



Cornell University. E. G. Lodematt. 



Notes. 



The Pennsylvania State Horticultural Society begins its 

 thirty-fourth annual meeting at Harrisburgh to-day, and con- 

 tinues for three days. Special attention will be given to re- 

 ports on the peach-yellows and plant diseases in general. 



Among the fancy fruits for sale now in the market of this 

 city are Gros Colman grapes, imported from England, which 



