August 19, 1896.] 



Garden and Forest. 



337 



seed has given us a nice lot of plants that promise to bloom 

 later. It should be stated that these Pennisetums are not 

 hardy, but can be easily wintered over with Tritomas and other 

 half-hardy plants of similar nature. Beds of ornamental 

 Grasses are very striking in suitable positions as isolated beds 

 on the turf. Arundo donax and its variegated form, the three 

 Eulalias (E. variegata, E. zebrina and E. univittata), the Penni- 

 setums, and as a margin Ophiopogon Jaburan variegatum, are 

 all admirable. This last is very beautiful, and perhaps the 

 prettiest hardy variegated plant we have, and, though not a 

 Grass, is very similar in appearance until the pretty spikes of 

 blue flowers appear. 



Spiraea Anthony Waterer is doing equally as well here as in 

 its birthplace. Mr. Waterer remarked last year that its color 

 was said to be not so good as when first exhibited, and the 

 doubt presented itself that, perhaps, our hot sun might tend to 

 fade the (lowers, but no such effect is apparent. Very small 

 rooted cuttings procured last spring are now flowering from 

 every little twig, but next year, when the plants are stronger, 

 we may expect to see it at its best. It is a dwarf shrub, but 

 will prove very valuable for use as a marginal plant in deco- 

 rative shrubbery, or even for summer bedding ; it flowers 

 perpetually. 



Our greatest success this season has been with border Pent- 

 stemons treated as annuals. It was noted earlier in the year 

 that this was the method now adopted by English growers, 

 instead of keeping them over as rooted cuttings. The flower- 

 spikes are very numerous now and will continue for some 

 time in succession. It is a great satisfaction to know this, 

 for many would grow them if it were known that the plants 

 need not be wintered over. I doubt if the old plants will prove 

 hardy, although the parents of this race are native North 

 American plants ; yet their identity is not easily traced now 

 after about seventy years of hybridization. The colors vary 

 from pure white to deepest crimson and purple, and the spikes 

 resemble those of Foxgloves, but the flowers are in this strain 

 much larger ; the only thing they seem to insist on is rich 

 moist soil, and we hope to mature seeds for a larger display 

 another season. 



South Lancaster, Mass. E. O. Or pet. 



Solanum Wendlandii. — Last year this plant was very fine 

 in the greenhouse later in the season, but was too rampant 

 for any but a very large structure, so we have this year tried 

 it out-of-doors in the border, where it has been in bloom 

 during the past few weeks, and will a little later make a fine 

 display ; each small shoot has a terminal flower-cluster of the 

 prettiest shade of lavender-blue, and as the plant is hard- 

 stemmed it is easily wintered over and may be set out again 

 year after year. It is a native of Central America, and the 

 most beautiful of all flowering Solanums known to cultivators. 

 We find it easy to propagate from young shoots taken from 

 the plant grown in the greenhouse ; those taken from strong 

 growth of a planted out specimen last fall did not root 

 owing to the abundance of sap in them. It is best to take 

 them from pot-plants and root them in an open bed of sand ; 

 in the propagating-case all will rot off. 



South Lancaster, Mass. E. 0. O. 



Correspondence. 



The Compass Plant. 

 To the Editor of Garden and Forest : 



Sir, — Is it true that there is on the prairies a Compass Plant, 

 which is a safe guide for persons who get lost? I mean, do 

 the leaves of this plant always point north and south so accu- 

 rately that it would be a safe guide for one who was lost on the 

 trackless prairie ? 



New Brunswick, N.J. o. 



[This letter was referred to the Rev. E. J. Hill, of 

 Chicago, who is familiar with the flora of this region, and 

 writes as follows : 



"The Compass Plant, Silphium laciniatum, may be 

 taken as a fair guide for distinguishing a general north and 

 south, from an east and west direction. There is a ten- 

 dency in the leaves to polarity, so there is also in the 

 Prairie Dock, S. terebinthinaceum, which, so far as I know, 

 has not been spoken of as a Compass Plant. And yet if 

 one runs his eye over a field where these plants occur he 

 would probably find seventy-five per cent, of them with 

 their edges pointing in a north-south direction. But in 

 both cases it is necessary to take into account the age of 



the plant, and even the wetness or dryness of the season. 

 It is the young plants which show the polarity best, or the 

 leaves which become the radical leaves of the flowering 

 plant. These twist more or less on the petioles, so as to 

 present their faces to the east and west. But when the 

 flower-stalk arises they are liable to drop away in various 

 directions, some plants in a way so disorderly that no use 

 could be made of them as a guide, others keeping their 

 polarity very well. This is the case also, but in a less 

 degree, with plants not sending up a flower-stalk, but 

 whose leaves at the season are large and heavy. Those 

 standing up stiffly show the best polarity, some quite 

 effectually. The sessile leaves of the flower-stalk so twist 

 the lower portion as to have the edges near the extremities, 

 or the upper half, up and down, and with the meridional 

 tendency. But this is hardly more so in the Compass 

 Plant than in the stem-leaves of the Prickly Lettuce, Lac- 

 tuca scariola, which, when standing in the full sunlight, 

 twist in a similar way and have the meridional tendency. 

 In a dry season, or with a lessened production of paren- 

 chyma, there is a diminished polarity. Professor B. D. 

 Halsted (Botanical Gazette, July, 1887, page 161) has also 

 noted this. In the cases he mentions the parenchyma was 

 so reduced that the polarity was virtually destroyed, and 

 the leaves would be useless as a guide. The way to use the 

 plants as a guide, so far as I have observed, would be to 

 take the mean of many observations. By doing so one 

 might approximately, or, in cases, quite accurately, hit upon 

 north and south. 



"Professor C E. Bessey (A?nerican Naturalist, August, 

 1877, P a ge 486) has some accurate observation on this 

 plant, with instructive tables showing the amount of varia- 

 tion. Of ninety-three leaves taken but one was accurately 

 north and south. All the rest deviated from 15' to 89 30', 

 virtually east and west. He says : 'Taking the bearings 

 of all the leaves observed we find that about thirty per 

 cent, did not vary more than five degrees, forty-two per 

 cent, not more than ten degrees, and ninety per cent, not 

 more than forty-five degrees from the meridian.' Dr. 

 Engelmann ( Works, page 533, an extract from The Gar- 

 deners' Chronicle, February 26th, 1S81), after describing the 

 arrangement and position of the leaves of the plant, 

 gives his opinion of their polarity by a reference as fol- 

 lows : 'Sir Joseph Hooker's remark about the appearance 

 of a plain covered with this Silphium from a railroad train 

 is quite correct, and any change in the direction of the road 

 becomes visible at once through the altered appearance of 

 the leaves of the Compass Plant.' This indicates a degree 

 of reliability on its guiding power.'' — Ed.] 



Rhododendron maximum in Connecticut. 

 To the Editor of Garden and Forest : 



Sir, — It is not generally known that there are at least three 

 stations in the state of Connecticut where Rhododendron 

 maximum thrives with luxuriance under conditions which are 

 apparently most congenial. Such a group exists near the 

 town of Milton, Litchfield County. A visit to this place when 

 the plants were in flower gave me an opportunity to observe 

 a truly wonderful sight. The site is a thickly wooded swamp 

 well up in the mountains, where forages, apparently, there Ins 

 been accumulating a peaty formation until the soii is entirely 

 of vegetable origin for a depth of at least six to eight feet, and 

 so soft and yielding that the larger growth of Hemlock, Yellow 

 Birch and Black Birch, Black Ash, American Elm, Red Maple, 

 etc., find no sufficient support, as is clearly shown by the 

 many that have been blown down, and the others that do not 

 stand perpendicularly. I was informed that this basin does not 

 overflow, neither is there standing water in sight, but the soil 

 has the appearance of having grown above the water-level by 

 slow accumulations, and now acts like a sponge, keeping moist 

 continually by absorption, while the heavy tree-growth over- 

 head tends to maintain an equable temperature. It is suffi- 

 cientlymoist to maintain a most vigorous growth of Sphagnum 

 and other moisture-loving Mosses, many of the woods Ferns, 

 Boxberry, Gold Thread, Partridge-berry, etc. 



This group of Rhododendrons occupies an area of about 



