8 MASS. EXPERIMENT STATION BULLETIN 435 



dust containing naphthaleneacetic or indolebutyric acid preceded by treatment 

 with the latter in solution; but the solution alone, a relatively low concentration, 

 was of no benefit (22). 



Cuttings were usually treated by the writer immediately after they were taken 

 and just before they were inserted in the rooting medium. In one case cuttings 

 taken from two trees on February 2 were first treated with indolebutyric acid 

 200 mg./l., 5 hr. or the same followed by Hormodin No. 3 nine weeks after their 

 insertion in the rooting medium. There was no rooting of the cuttings which 

 received this delayed first treatment although cuttings from these two trees 

 treated earlier and immediately after they were taken rooted 20 or 13 percent 

 following the solution immersion treatment, 37 or 13 percent following the com- 

 bination treatment. 



Powder-dip treatments were applied in the usual manner to the bases of cut- 

 tings- which had been dipped in water immediately previously. Cuttings which 

 were treated by the solution-immersion method were set loosely in beakers, not 

 bound by elastic bands or otherwise. 



As may be seen by reference to Table 4 and several of the other tables, rooting 

 was often, although by no means always, improved by solution-immersion treat- 

 ment with indolebutyric acid 200 mg./l., 5 hours. A longer period of immersion 

 or immersion for four hours or less in a solution of this concentration gave no 

 better results and more often they were inferior. And a dilution of 200 mg./l., 

 5 hr. usually gave better results than did a dilution of 100 mg./l. for a longer time. 



Rooting of cuttings which responded to this treatment was also improved 

 (see Tables 1, 2 and 4) by powder-dip treatment with Hormodin No. 3, but 

 cuttings which failed to show much response to indolebutyric acid, in solution 

 were not much affected by Hormodin No. 3. Thus cuttings taken from three 

 trees en February 1 failed to root without treatment and rooted only 8 to 22 

 percent after either indolebutyric acid 200 mg./l., 5 hr. or Hormodin No. 3. 

 Hormodin No. 2 sometimes gave good results with cuttings from the responsive 

 trees (see Table 3), but more often it was less effective than Hormodin No. 3. 



Good results (see Tables 3 and 4) were obtained with some cuttings by treating 

 them with a Hormodin dust following a solution-immersion treatment. But 

 here again it was usually possible to distinguish between trees the cuttings of 

 w'hich were responsive to either or both and those which were responsive to 

 neither. 



Rooting was also improved in some cases (see Tables 2, 3, and 4) by naphtha- 

 leneacetic acid 100 mg./I., 5 hr., but rarely if ever did this treatment give any 

 better results than indolebutyric acid 200 mg./l. similarly used. And combina- 

 tions of naphthaleneacetic and indolebutyric acids in solution gave no better 

 results than either alone. Results were not so good with naphthaleneacetic acid 

 50 mg./l. as with 100 mg./l. 



Cuttings taken February 21 from one tree rooted 13 percent without treat- 

 ment, 43 percent after treatment with indolebutyric acid 8 mg./gm. talc, and less 

 well, only 20 percent, after treatment with indolebutyric acid 8 mg./gm. Fermate.^ 



Cuttings taken March 22 rooted not at all without treatment; 27 percent after 

 treatment with indolebutyric acid 200 mg./l., 5 hr. ; and no better, 25 percent, 

 after treatment wnth 200 mg./l., 5 hr., followed by a powder-dip treatment with 

 Fermate. 



Fermate gave somewhat better results with some cuttings (see Tables 3 and 4) 

 when combined with a Hormodin powder in the proportion of 1:1 by volume. 

 Cuttings from one tree rooted well when treated with Fermate alone or preceded 

 by solution-immersion treatment. But (see Tables 3 and 4) the results were no 

 better than with indolebutyric acid 200 mg./l., 5 hr., used alone. 



"An organic fungicide containing ferric dimethyl dithiocarbamate. 



