﻿Halsted : Mvcological Notes. 333 



During the past year while visiting various fields in a study of 

 the rust {Puccinia asparagi DC.) it has been observed that in 

 many instances asparagus plants otherwise entirely free from the 

 rust would have one or more diseased tufts and these assumed an 

 appearance that at once suggested the "witches brooms" of cedar 

 and cherry trees, although upon a much smaller scale. 



There seems to be no order as to their appearance, as some- 

 times they are near the tip of the main branch and again they are 

 here and there along the stem as malformed lateral shoots. The 

 engraving (figure 2) shows a small branch upon which there are 

 two rusted twigs. The one at a is the lowermost branch of a 

 side shoot, all other portions of which are normal. At b is shown 

 a second rusted and dwarfed branch, while next above it is a nor- 

 mal twig. The differences between the infested and healthy 

 branches are well shown in the engraving made from a sun print 

 of the subject and one-third reduced. In the diseased parts the 

 "leaves" while more numerous are not about half the ordinary 

 size and there is a strong tendency to produce side branches and 

 thus form the " broom." Sometimes the diseased branch develops 

 so that there is a decided tuft, which tends to grow upright even 

 if the main branch bearing it is more or less inclined. This ten- 

 dency for a fungous infested branch to be perpendicular is as well 

 illustrated in these "brooms" as in case of the prostrate euphor- 

 bias attacked by Aecidium or the common purslane when badly 

 infested with white mould [Cystopus portulacac). 



In case the asparagus plant is inoculated as its young succu- 

 lent stems come above ground there is but little chance of " brooms" 

 to form and they therefore are generally met with in beds where 

 the spores have not reached the plants until they are approaching 

 f ull growth. The local disturbance indicates a local inoculation 

 and the malformation shows how rapidly the fungus spreads in 

 the host. 



The Rose Speck.— Recently it was my privilege to visit a brand 

 n ^" greenhouse in which a middle bed of roses had recently been 

 ^ out. The leaves of these plants were nearly all dotted over 

 With minute circular black specks smaller than the head of a bank 

 1 and jet black. The gardener was exercised oxer the idcle.i 

 a Ppearance of these numerous specks and desired a preventive. 



