442 



Garden and Forest. 



[Number 186. 



With such advantages, may one not look forward confidently 

 to the fulfillment of a belief that this will become a region of 

 delight to the lover of landscape-gardening ? 



Boston, Mass. Will. Miliot, Jr. 



Pitch Pine from Seed. 

 To the Editor of Garden and Forest : 



Sir,- — A large field, worthless for cultivation, almost pure 

 sand, in places a little loamy, is growing up with Bayberry, 

 Sweet Fern and Golden-rod. Would seeds of Pinus rigida 

 catch here, and if so, how should they be sown, or is there 

 any chance of success in using other tree-seeds, and if so, 

 what sorts — either deciduous or evergreen ? Expense is very 

 much to be considered. 



Providence, R. I. Bayberry. 



[Such land as our correspondent describes will quickly 

 produce a crop of Pitch Pine {Pinus rigida) ; but it often 

 possesses more plant-food than its natural plant-covering 

 would indicate, and such land will often grow White Pines, 

 Oaks and Chestnuts of a considerable size and value, as 

 the plantations made in East Greenwich, Rhode Island, by 

 Mr. Henry G. Russell demonstrate. The best way to plant 

 Pitch Pine is to sow the seed in the spring with an ordinary 

 seed-sower in shallow furrows four or five feet apart each 

 way ; but, as the surface of this particular piece of ground 

 is already more or less covered with dwarf shrubs and 

 other plants, it would be cheaper to scatter the seed broad- 

 cast over the surface and take the chance of a sufficient 

 number germinating to cover the ground with plants. 

 White Pines are best transplanted when ten or twelve 

 inches high. It is a good plan to plant acorns of the White, 

 Red and Black Oaks and Chestnuts among young Pines, to 

 replace these in case they are destroyed by fire or other 

 causes, or to take their place after the Pines are cut. The 

 seeds of such deciduous trees can be quickly and cheaply 

 planted in holes an inch or two deep, made with an ordi- 

 nary walking-stick. The holes, after the seeds have been 

 dropped in, should be covered by a pressure from the foot, 

 which will make the soil compact over them. The seed- 

 ling Oaks and Chestnuts will exist for years under the dense 

 shade of the Pines, and will grow rapidly as soon as light 

 and air are admitted to them. — Ed.] 



Recent Publications. 



The relation of electric light to vegetation is a subject of 

 interest to horticulturists, both from a scientific and econom- 

 ical standpoint, and therefore we are glad to see in Bulletin 

 No. 30, of the Cornell Experiment Station, an account of what 

 Professor Bailey accurately calls " Preliminary Studies of the 

 Influence of the Electric Arc Lamp upon Greenhouse Plants." 

 The bulletin contains some forty pages, and therefore we are 

 able to give only a condensed account of the methods em- 

 ployed and the conclusions readied. 



A forcing-house, twenty feet by sixty, was divided into equal 

 portions by a partition, one of which was left under ordinary 

 conditions of sunlight during the day and darkness at night. 

 The other had sunlight during the day, and in the first series 

 of experiments an electric light was suspended from the peak 

 of the house, which was run all night from dusk to daylight. 

 The same kind of vegetables were planted in each compart- 

 ment, and, as a rule, the general effect of the electric light was 

 to hasten maturity, and this acceleration was greater as the 

 plants were nearer to the light. This tendency was particu- 

 larly marked in Endive, Spinach, Cress and Lettuce, so-called 

 "leaf-plants." They ran to seed before edible leaves were 

 formed, and the leaves of those near the light were small and 

 curled. The Spinach under electric light matured good seeds, 

 while that in the dark house was still making large edible 

 leaves with no indication of flower-stalks. The microscope 

 showed that there was apparently the same amount of starch 

 in the plants of each compartment, though the starch-grains 

 of the plants under the electric light were larger, had more 

 distinct marking and gave a better color-test — that is, they 

 seemed more perfectly developed than in the others. Lettuce 

 behaved in the same way, most of the plants being killed out- 

 right for three feet on either side of the lamp soon after they 

 came up, and the plants which survived were seriously 

 injured, the leaves being curled and small. The plants in- 



creased in stature and vigor and size of the leaves as they 

 were at greater distances from the lamp, and those nearest the 

 lamp made the most of their leaves early in their growth. 

 The plants at five weeks all ranged from a little more than 

 one inch to a trifle over two inches high, while the average 

 height of the plants in the dark house was two and one-quar- 

 ter inches, and they were much more vigorous and had larger 

 and darker leaves. In two varieties of Cress the plants under 

 the electric light were in bloom although they were small and 

 sickly, while those in the dark house were strong and vigor- 

 ous, with good leaves and no blossoms. Endive gave prac- 

 tically the same results. It chanced that two rows of plants 

 were parallel to each other in the lighted house, but one was 

 shaded by an iron post only an inch and a half in diameter, 

 while the other stood in the full rays from the arc. Two 

 months after planting, the average weight of the plants in full 

 light was about fifty grains, and that of the plants in the shade 

 of the post was ninety-four grains, while the average plant 

 in the dark house of the same age weighed 575 grains, and had 

 larger leaves and of a better color than those grown in the 

 other apartment. Young Radish-plants seemed strongly at- 

 tracted by the electric light, and in the morning they all leaned 

 at an angle of from sixty to forty-five degrees toward the lamp. 

 During the day-time they all would straighten up again, but 

 would reach out for the lamp on the succeeding night, and this 

 was repeated until the roots began to swell and the plants be- 

 came stiff. When the Radishes were large enough to market, 

 the entire plants in the light house were lighter by nearly half 

 than those in the other compartment, while the tubers were 

 lighter by more than fifty per cent., and there were three 

 times as many of these large enough for market in the dark 

 house as there were in the light house. All these results are 

 made very striking in the bulletin by reproductions of pho- 

 tographs, which show clearly the differences, while chemical 

 analysis showed that plants under the electric light had reached 

 a greater degree of maturity than those under normal con- 

 ditions. 



Altogether it was plain that the plants in the lighted house 

 were injured, and the question was, whether this was due to 

 the quality of the electric light or to the fact that the plants 

 were in continuous light during the entire twenty-four hours. 

 To settle this point some plants were covered during the day 

 so as to receive no sunlight, although they were well venti- 

 lated, and the covers were removed so that they could receive 

 electric light for twelve hours during the night. But under 

 these conditions Radishes made but a sickly growth, assumed 

 a faint green color, and died within three or four weeks. An 

 experiment of the same character was now conducted on a 

 larger scale when the hours of sunlight were about equal to 

 those of electric light, and the plants were shaded, not com- 

 pletely, but only from the direct rays of the sun, so that they 

 could receive diffused light. They quickly died. Lettuce, 

 Beans, Corn and Potatoes repeated the same lesson. Plants 

 which had already been well started behaved in the same 

 manner, so that it seems to be established that, within the 

 range of an ordinary forcing-house, a naked arc-light running 

 through the night is injurious to some plants, and that it was 

 not found profitable in any case. 



The fact, however, that the light hastened maturity or seed- 

 bearing suggested that some modification of the light might 

 be useful under certain conditions, and, therefore, an experi- 

 ment was made with a protected light running through the 

 night ; that is, a white opal globe was placed over the lamp, 

 and, for five weeks, experiments similar to those formerly de- 

 scribed were carried on. The effect of this modified light 

 was much less marked than that of a naked light, the plants 

 showed less tendency to run to seed, and were not so much 

 affected by proximity to it. Lettuce, however, was decidedly 

 better under the shaded electric light. This fact that the 

 Lettuce, as well as the leaves of Radishes, grew larger under 

 the subdued light than in ordinary conditions, indicated that 

 there might be conditions under which artificial light could be 

 made profitable to the gardener, and therefore an experi- 

 ment was made, during the early part of the present year, 

 with the naked light running for a portion of the night only. 

 The house was arranged as before, but the lamp was con- 

 nected with the street-lighting system, so that it never ran on 

 moonlight nights, and only for a few hours on dark nights. 

 Under these conditions Lettuce was greatly benefited. The 

 plants were fit to market two weeks earlier in the lighted com- 

 partment than they were in the other. They were on the 

 benches only forty-four days before the first heads were fit to 

 sell, and during this time there were twenty nights in which 

 the electric light had not been run, and during the whole time 

 there had been but eighty-four hours of electric light, which 



