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Bulletin - Massachusetts Agricultural Experiment Station (Volume no.379-398) online

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soil after treatment with indolebutyric acid (25 mg./l., 16 hr.), 40 per-
cent without it.

Ilex cornuta. Summer cuttings root well if taken after young leaves have
become dark green (110). Cuttings have also rooted well when taken
as late as January (44). Rooting was hastened by treatment with a
40-unit solution of Hormodin A, 100 percent of the treated cuttings
rooting in 35 days (117), or with indolebutj^ric acid 30 to 80 mg./l.,
24 hr. (125).

Ilex crenata. Cuttings, torn from the plant at the base of the current
year's growth (61), root readily if taken in fall and winter (15, 107), even



PROPAGATION OF TREES AND SHRUBS 23

more quickly if taken in summer (125). They root well in sand (125),
probably better in sand-peat (15), and respond to treatments with indole-
butyric acid (20 mg./L, 24 hr., or 2 mg./gm. talc) (61). Cuttings taken
here in November rooted 100 percent without treatment, in half the time
with it. Cuttings taken here in January rooted 89 percent in 15 weeks
without treatment, 100 percent in 6 weeks with treatment. Rooting of
summer cuttings was similarly hastened by treatment (125), and treated
fall cuttings developed larger root systems than the untreated (47).

Ilex glabra, inkberry. Cuttings may be taken from July or August to as
late as January (15). They responded to treatments with indolebutyric
acid (20 mg./L, 24 hr., or 2 mg./gm. talc) (61). Summer cuttings rooted
90 percent in sand with or without indolebutyric acid (50 mg./l., 4 hr.),
but they rooted more rapidly with it (125). Rooting of summer cuttings
was also hastened by treatment with 10 mg./l., 24 hr. (57).

IlcA- opaca, American holly, is not difficult to propagate by late summer or
fall cuttings, taken after the new growth has become dark green (76) and
made with the basal cut at the base of the current year's growth, only 3
or 4 leaves nearest the tip being retained (76, 129). They may be taken
as late as December (45), but August and September are better months
{Z2)). Sand (29, 101) or sand-peat (57) are good rooting media, better
than sandy soil. It is well to insert cuttings at an angle, the leaves al-
most flat on the rooting medium (129). Treatments with indolebutyric
acid (40 to 80 mg./l., 24 hr., or 12 mg./gm. talc) are beneficial (61). Cut-
tings taken here in late August rooted 96 percent after treatment (50
mg./L, 20 hr.), 49 percent without it. Rooting of winter cuttings was
more improved by 30 or 50 mg./l. than by greater concentrations (57).
October cuttings rooted 90 percent in 2 months without treatment and in
1 month after treatment (100 mg./L, 18 hr,) (125).

Ilex rugosa. Untreated cuttings taken here in November rooted 100 percent
in sand-peat in 5 months. Their rooting was hastened by 2 months, but
not otherwise affected, by treatment with indolebutyric acid (100 mg./L,
18 hr.).

Ilex verticillata, black-alder. Summer cuttings and those of harder wood
rooted better in peat moss than in sand (14, 66). Cuttings rooted in 18
days at 80° F., much more slowly at 59° F. (126). Treatments with indole-
butyric acid (40 to 80 mg./L, 24 hr., or 12 mg./gm. talc) are beneficial (61).

Ilex voniitoria, yaupon. Cuttings, untreated, rarely root, but they rooted
after treatment with naphthaleneacetic acid, 1:1000, in talc (96).

Itea virginica is easily propagated by softwood cuttings. Taken here about
July 1, they rooted 100 percent in sand in 4 weeks whether or not they
were treated.

Jasmimim nudiflornm. winter jasmine, is readily propagated by cuttings
taken in late summer (80, 106) and inserted in sand (105), sand-peat (87),
or sandy soil (80).

Juniperus, juniper. Cuttings respond to treatments with indolebutyric acid.
Effective concentrations are 40 to 60 ing./L, 24 hr., or 5 to 12 mg./gm. talc
for mountain juniper (49); 40 to 80 mg./L, 24 hr., or 12 mg./gm. talc for
Chinese juniper. Pfitzer juniper, creeping juniper, savin, red cedar, /. con-
ferta, and /. excelsa (61). Cuttings of /. excelsa, creeping juniper, and
Pfitzer juniper root better in sand-peat than in sand (14). A few of the
species are separately referred to below.



24 MASS. EXPERIMENT STATION BULLETIN 382

Juniperus chinensis var. Pfitzeriana, Pfitzer juniper. Cuttings are usually
difficult to root in good percentages (103), but untreated cuttings rooted
100 percent in sandy soil in 4 months, 86 percent in sand in 11 months,
when taken here in August. November cuttings have often rooted better
than those taken later (13, 31, 57) but they sometimes root as well if
taken in December and January (103). Rooting of cuttings taken here
in December was improved by treatment with indolebutyric acid
(50 mg./l., 24 hr.), 100 percent of the treated cuttings rooting in 5 months,
but that treatment apparently injured August cuttings. Cuttings taken
in early February rooted, in about 15 weeks, 20 percent without treatment,
92 percent with Hormodin No. 3 (103).

Juniperus communis, common juniper. Cuttings of prostrate juniper rooted
about equally well when made of wood one,, two, or three years old, but
wood two or three years old results more quickly in larger plants (69). Cut-
tings of /. communis var. Ashfordii which were taken here in December rooted,
without treatment, 50 percent in sand or sand-peat, 80 percent in sandy
soil; and those which had been treated with indolebutyric acid (100 mg./l.,
22 hr.) rooted 60 percent in sand, 90 percent in sandy soil. Taken here in
December, cuttings of Irish juniper treated with indolebutyric acid (100
mg./l., 20 hr.) rooted 75 percent in sand in 6 months ,100 percent in sandy
soil in 3 months; and untreated cuttings rooted as well but more slowly.

Juniperus horizontalis, creeping juniper. Untreated cuttings of Waukegon
juniper rooted more than 90 percent in 8 weeks when taken here in No-
member and December. They also rooted well if taken in summer (14),
but summer cuttings of the variety plumosa rooted less well than fall and
winter cuttings (123). Fall and winter cuttings root so readily that treat-
ments may be without much effect (57, 83) except sometimes in increasing
the numbers of roots on each cutting (125). A higher concentration of
indolebutyric acid is suggested for cuttings in the first stages of dormancy
than for those taken in the winter (57}.

Juniperus procmnbens. Untreated cuttings rooted more than 90 percent in
sand-peat when taken here in early November, less well if taken in Feb-
ruary.

Juniperus Sabina, savin. Cuttings rooted better when taken in late fall or
early winter than when taken later (13,31). Untreated cuttings of the
variety tamariscifolia taken here in late November rooted 90 to 100 percent in
sandy soil or sand-peat, less well in sand.

Juniperus virginiana, red cedar, and its varieties have not been easily prop-
agated by cuttings even after treatment (17, 18, 57, 83). Cuttings of the
variety Kosteri taken here in December failed to root without treatment, but
cuttings treated with indolebutyric acid (100 mg./l., 20 hr.) rooted 58
percent in sandy soil, less well in sand.

Kalmia lafifolia. mountain laurel, is considered difficult to propagate by
cuttings (73, 113), but there was 100 percent rooting of untreated Novem-
ber cuttings in a mixture of cinders and peat, 1:1, with bottom heat at
80° F. (29). Sand-peat is also a good rooting medium (51). Rooting of
late July cuttings, poor at best, was more improved by indoleacetic acid
(90 mg./l., 24 hr.) than by indolebutyric acid (88). Rooting of early-
winter cuttings was also improved by indoleacetic acid (100 mg./l., 48 hr.);
66 percent rooting with it, 12 percent without it, in 5 months (113). Leaf-
bud cuttings gave better results than ordinary stem cuttings and, taken
in late July, leaf-bud cuttings rooted 80 percent in 19 weeks after treat-
ment with indolebutyric acid (90 mg./l., 24 hr.), 20 percent without it (88).



PROPAGATION OF TREES AND SHRUBS 25

Kalmia polifolia. Untreated cuttings rooted 100 percent in 3 months in sand-
peat when taken here in mid-September, much less well when taken in
mid-July.

Kerria japoiiica. Untreated softwood, July, cuttings rooted 100 percent in
sand-peat, less well in sand (14). Treatments with indolebutyric acid (57)
and indoleacetic acid did not increase percentages which rooted, but root-
ing was hastened by indoleacetic acid (33 mg./l.) (113).

Keteleeria Davidiana. December cuttings rooted 100 percent in 7 weeks
after treatment with indolebutyric acid (100 mg./l., 24 hr.), not at all
meanwhile without treatment (109).

Kolkwifsia amabilis, beauty-bush. Softwood, summer, cuttings, made of the
tips of shoots (48) usually root well in sand (105) or sandy soil (80).
Rooting of June or July cuttings was hastened by treatment with indole-
butyric acid 12 mg./gm. talc or 20 mg./l., 24 hr. (49), or 60 mg./l., 4 hr.
Cuttings given the last named treatment rooted 100 percent in 34 days
(125).

Laburnum anagyroides, golden-chain. Softwood, July cuttings, made with
the basal cut at a node, rooted 100 percent without treatment (14).

Larix sibirica, Siberian larch. There was some rooting of softwood, early
summer, cuttings treated with indoleacetic acid (50 mg./l., 24 hr.), not of
the untreated; but cuttings of slightly harder wood, taken two weeks
later, failed to root whether or not they were treated ' (65).

Lavandula officinalis, lavender. Summer cuttings, untreated, root readily
in sandy soil (80, 105).

Lespedcca. Cuttings of L. Thunhcrgii taken here in early October rooted
66 percent in sandy soil after treatment with indoleacetic acid (100 mg./l.,
18 hr.), not at all without it. The species is also propagated by cuttings
taken in summer and rooted in sandy soil (80).

Leucothoe Catesbaci is easily propagated by softwood cuttings (67), made
with the basal cut a half inch below a node (14). July cuttings rooted
100 percent in sand-peat in 12 weeks without treatment or in 10 weeks
after treatment with indolebutyric acid (10 mg./l., 24 hr.) (88). This
species is also readily propagated by leaf-bud cuttings whicli, taken in late
June, rooted 100 percent in 10 weeks without treatment (90).

Libocedrus decwrens, incense cedar. Untreated cuttings taken here in No-
vember remained alive but unrooted in sand-peat for 15 months. Some
of them were then treated with indolebutyric acid and all were replanted.
Those treated with 150 mg./l., 24 hr., rooted 100 percent in the next 9
weeks. Results were a little less good with 75 mg./l. and only 50 percent
of the untreated rooted in a total of 22 months.

Ligustrum. Privets can be propagated by softwood, summer, cuttings in
sand or by hardwood, fall, winter, or early spring cuttings. Early summer
cuttings of Japanese privet rooted best if made of growing tips, not older
wood (125). There are sometimes more roots per cutting or more rapid
rooting following treatments with indolebutyric acid (57, 83, 117), optimum
concentrations for California privet being 80 mg./l., 24 hr., or 12 mg./gm.
talc (61). For privets in general, naphthaleneacetic acid is more eflFective
(49). Concentrations of 60 mg./l., 24 hr., or 1:250 in talc liastened root-
ing of September cuttings of L. cnmpactuni (96).
Lindera Benzoin, spice bush, is sometimes propagated by summer cuttings



26 MASS. EXPERIMENT STATION BULLETIN 382

made of half-ripe young shoots (80), but they do not ordinarily root very
well (51).

Liquidambar. Cuttings of L. formosana, L. oricntalis (105), and sweet gum
(42) will root in sand if taken in summer and made of half-ripened wood
with a heel.

Liriodendron Tulipife\ra, tulip-tree. Propagation by cuttings has been con-
sidered impractical (105), but there was 52 percent rooting of untreated
July cuttings made with the basal cut a half inch below a node (14).
Rooting of summer cuttings, in sand-peat, was hastened by treatment with
indoleacetic acid in a relatively high concentration (87).

Lonicera, honeysuckle. Softwood, summer, cuttings of many species root
well in sand (44, 105) or sandy soil (7), and hardwood cuttings are also
used with good results. Untreated hardwood cuttings of L. Morrowii
rooted well when taken in April (13). Cuttings of L. pileata and L.
nitida, without treatment, rooted 100 percent in sandy soil in about 8 weeks
when taken here in December. Hardwood, early spring, cuttings of L.
coerulea (65) and Tatarian honeysuckle (40, 65) responded to treatment with
indoleacetic acid 50 mg./l., 48 hours for the former, 24 hours for the latter.
Rooting of November cuttings of L. Korolkozvii was more improved by that
acid (100 mg./l., 24 hr.) than by indolebutyric acid (83) but very dilute
S'olutions of the latter are effective with softwood cuttings. July cuttings of
L. nitida rooted 100 percent in 14 days after treatment with indolebutyric acid
5 mg./l., 24 hr. (57) and that treatment was followed by good rooting of
softwood, spring, cuttings of L. Maackii in 16 days (48). July cuttings of
L. fragrantissima rooted so well without treatment that treatments were of
no significant advantage (104), but the rooting of Tune cuttings of that
species was hastened by indolebutyric acid (10 mg./l., 24 hr.) (57).

Lycium, box-thorn. Untreated softwood, summer, cuttings of Chinese mat-
rimony-vine and L. ruthcnicimi root readily (42). Hardwood cuttings also
root well. Taken here in late March, buried in sand in a cold cellar for 3
weeks and then planted in the field, cuttings of L. rtithetiicum rooted 100 per-
cent in 9 weeks with or without treatment.

Madura pomifera, osage orange, can be propagated by softwood cuttings,
the basal cut a half inch below a node (14). July cuttings rooted 100 per-
cent in sand-peat in 42 days after treatment with indoleacetic acid (100
mg./l., 24 hr.), 32 percent without treatment (87).

Magnolia. These have not been considered easy to propagate by cuttings
{72)). Cuttings are made of soft wood, taken in summer (63, 67, 105, 124).
Sand is a good rooting medium (63, 87, 105) — better, at least for some species,
than sand-peat (14) and better, at least for M. Soiilangcana (27), than sandy
soil. A small heel is considered desirable (63). Untreated cuttings may
root slowly (124) or not in large percentages and treatments are worth while.
Cuttings of M. Soulangcana which were taken here in late June rooted 100
percent in 35 days after treatment with indolebutyric acid (50 mg./l. , 22 hr.),
32 percent without it. This treatment also improved the rooting of early
July cuttings of M. stcUata. August cuttings of M. liliiiora rooted 1(X) per-
cent in 49 days after that treatment, 21 percent without it, and rooting of June
cuttings of M. Kobus was improved by similar treatment with 80 mg./l. (125).
Malus, apple. Softwood cuttings of some species and varieties will root if
they are taken in late spring or early summer and if they are more than usually
well protected against wilting (42). Taken here in late June, cuttings of
M. atrosanguinea rooted 57 percent in sand-peat without treatment ; and cut-



PROPAGATION OF TREES AND SHRUBS 27

tings of M. arnoldiana rooted 60 percent after treatment with indolebutyric
acid (50 mg./L, 20 hr.), although not at all without treatment. Early July
cuttings of M. pumila var. Eleyi (the common apple is M. putnila) rooted 70
percent in sand after treatment with indolebutyric acid (50 mg./L, 4 hr.),
not at all without it (125). Cuttings of another variety rooted well after
treatment with naphthaleneacetic acid (20 mg./L, 24 hr.) if they were
taken in spring or early summer before growth had been completed (81).
There was no rooting of similar cuttings of Siberian crab whether or not
they were treated (113).

Hardwood cuttings of some varieties of the common apple, made of
wood in its first, second, or third year (126) will rout, but propagation in
this way has not in the past proved commercially practical (12). Cuttings
of Northern Spy taken in March rooted 25 percent in peat moss at 65° F.,
not at all in sand-peat or sand (66). Similar cuttings of Delicious failed
to root even after treatment (95). There was 75 to 100 percent rooting
of hardwood (November to February) cuttings of Rhode Island Greening
and Grimes Golden which were made of tips of the current year's growth,
treated with indolebutyric acid (40 mg./L, 24 hr.), and immediately buried
in moist peat moss, but no rooting of untreated cuttings (48, 49). At-
tempts to repeat this with cuttings of Mcintosh taken here in February
and March were unsuccessful. Best rooting, only 20 percent, was of
treated cuttings made of wood two years old or of tips of the newest
growth, but the rooted cuttings died when transplanted.

Myrica Gale, sweet gale, is easily propagated by softwood cuttings. Un-
treated cuttings which were taken here in late June rooted 85 percent in
sand in 57 days. July cuttings rooted 100 percent in sand-peat in 38 days
after treatment with indoleacetic acid (100 mg./L, 24 hr.), 60 percent
without it (87).

Ostnanthus ilicifoHus. Summer cuttings root readily in sand (105) or
sandy soil (80). Rooting was liastened by treatment with indoleacetic
acid (20 mg./L, 24 hr.) (113) or indolebutyric acid (150 mg./L, 4 hr.), but
untreated cuttings taken in late July rooted more than 90 percent (125).

Oxydendrum arboreum, sorrel-tree, can be propagated by softwood cuttings,
short side shoots with a heel (80). Late July cuttings rooted 80 percent
in sand-peat in 8 weeks after treatment with indolebutyric acid (90 mg./L,
8 hr.), less well in sand, and not at all in 8 weeks without treatment (88).

Pachistima. Cuttings of P. Canbyi and P. Myrsinites taken here in October
and November rooted more than 90 percent in sand-peat whether or not
they were treated. Softwood cuttings are also successfully taken in July
and rooted in sand (67).

Pachysandra terminalis is easily propagated by July and August cuttings
(106). Late June cuttings rooted 100 percent in 28 days after treatment
with indolebutyric acid (30 mg./L, 6 hr.), 60 percent without it (83.).
Concentrations effective with winter cuttings are naphthaleneacetic acid
20 to 100 mg./L, 24 hr., (47) and indolebutyric acid 20 to 40 mg./L, 24 hr.
or 5 to 12 mg./gm. talc (49).

Parrotia per ska. Summer cuttings rooted 100 percent in sand-peat in 38
days after treatment with indoleacetic acid (100 mg./L, 24 hr.), less than
50 percent without it (87).

Parthenocissus. Boston ivy and Virginia creeper are easily propagated by
softwood cuttings. Untreated August cuttings of the former rooted 90
percent in 20 days and treated cuttings rooted no better (16).



28 MASS. EXPERIMENT STATION BULLETIN 382

Passiflora racemosa, passion-flower. Softwood cuttings taken here in July
rooted 90 percent in sand in 8 weeks after treatment with indolebutyric
acid (50 mg./l., 24 hr.), 40 percent if untreated. Sandy soil may also be
used as a rooting medium (80).

Periploca. Softwood cuttings of silk-vine and P. sepium taken here in early
August rooted 100 percent in sand-peat in 4 weeks with or without treat-
ment. Late August cuttings of silk-vine, in sand, failed to root in 4 weeks
without treatment but rooted 70 percent after powder-dip treatment with
indolebutyric acid, 1:500 (104).

Philadelphus, mock-orange. Softwood. July, cuttings of many species root
well without treatment (44, 66, 116, 125) ; better sometimes in sand-peat that
in sand (14, 66). The only response of P. grandiUorus to treatment was more
roots on each cutting (125). Rooting of cuttings of P. cymosus (125) and
P. coronarius (83) was hastened by treatment with indolebutyric acid, the
former responding to 30 to 80 mg./l. , 4 hr., and the latter to 50 mg./l.,
20 hr.

Photinia. The species can be propagated by fall or late summer cuttings,
short side-shoots, with a heel (105). Fall cuttmgs of P. glabra rooted 100
percent in 62 days after treatment with indolebutyric acid (50 mg./l., 18 hr.),
5 percent without it (20). Summer cuttings of P. scrrulata rooted 20 percent
without treatment, 80 percent after treatment with indolebutyric acid
(20 mg./l., 6 hr.) (119).

Physocarpus opulif alius, ninebark, is easily propagated by softwood, summer
cuttings. They rooted better in sand-peat than in sand, better at 60° F.
than at 70° F. (116). Cuttings of harder wood are also successfully
used. Taken in November, they rooted 80 percent in 53 days without
treatment and only a little better after treatment with indolebutyric acid
(50 mg./l., 40 hr.) (16).

Picea Abies, Norway spruce. Cuttings rooted better if taken in November
than if taken in late winter (38), better if taken in December than if taken
in spring, summer, fall, or later in the winter (24). Best results have followed
the taking of cuttings, laterals rather than terminals (109), from the lower
in preference to the upper part of trees (35). Cuttings root with less diffi-
culty than do those of most spruces (106) ; and cuttings of the varieties nigra,
Maxwellii, Clanbrasiliana, and Ohlendorfii which were taken here in December
rooted at least 70 percent without treatment, no better and not always so
well with it. Treatments for 24 hours with solutions of indoleacetic (41)
or indolebutyric acid (24) failed to improve rooting significantly and
similar treatment with water alone was apparently somewhat injurious
(24). Powder-dip treatment with indolebutyric acid (4 mg./gm. talc)
caused some injury in many cases (24), but rooting was somewhat im-
proved by indoleacetic acid in talc (41). November cuttings, made with
the basal cut somewhat above the base of the current year's growth and
planted immediately in a mixture of equal parts of sand and peat humus in
shaded outdoor frames, rooted about 50 percent without treatment, 82
percent in 10 months after treatment with indoleacetic acid ( 5mg./gm.
talc) (39). Treated cuttings in that experiment rooted less well in sand,
but untreated cuttings from trees 40 years old, made with the basal cut
not far above the base of the current year's wood, rooted 80 percent in
sand; better, with less rotting, in open benches in a warm greenhouse
than in a closed sweat bench (24).



PROPAGATION OF TREES AND SHRUBS 29

Picea glauca var. conica. Taken here in early December, cuttings in sand-
peat rooted 39 percent without treatment, 92 percent after treatment with
indolebutyric acid (70 mg./l., 20 hr.), with results less good in sand. Late
winter cuttings respond to treatment with 40 to 60 mg./l., 24 hr., or 2 to
12 mg./gm. talc, or, by the concentrated solution-dip method, 4 mg./cc.
(49). Cuttings are taken in summer in England (7).

Picea Omorika, Serbian spruce. Suggested treatments with indolebutyric
acid are 40 to 80 mg./l., 24 hr., or 12 mg./gm. talc (61).

Picea pungens, Colorado spruce. Best rooting was of cuttings taken in Feb-
ruary (61, 67, 127). Summer proved to be a poor time to take them (126).
April cuttings rooted 80 percent in 8 weeks after treatment with indole-
acetic acid (100 mg/L, 24 hr.), but bud development was retarded for a
few months following (109). Indolebutyric acid (40 to 80 mg./l., 24 hr.,
or 12 mg./gm. talc) may also be used (61). Cuttings rooted better in
peat moss than in sand (44), but cuttings of the variety Kosteriana rooted
well in sand (66).

Picea sitchensis, Sitka spruce. Late winter cuttings made of the current
year's wood rooted 100 percent in sand-peat in 60 days after treatment
with indolebutyric acid (25 mg./l., 24 hr.), less well if taken in fall or
early winter or if not treated (43).

Pieris. P. japonica and P. Uoribunda can be propagated by cuttings taken in
July or August when the wood is nearly ripe, made with the basal cut about
one-fourth inch below a node (67), and inserted in sand-peat (80, 88). July
cuttings of P. japonica rooted 80 percent without treatment, 100 percent in 6
weeks with treatment (88). Indolebutyric acid (10 mg./l, 24 hr.) has
given good results with that species (61), which is also easily propagated
by leaf-bud cuttings taken in early summer (89).

Pinus Strobus, white pine. Cuttings, treated or not (61), have not often
rooted well if obtained from mature trees or, in fact, from trees more
than three or four years old (24, 42, 109), but cuttings from older
trees can be rooted (24, 28, 74, 94). Cuttings which were taken
here in mid-March from a tree about thirty years old did not root without
treatment and rooted poorly or not at all, with or without treatment, if
taken from the upper part of the tree; but cuttings from the lower part of
the tree rooted 70 percent in sand-peat in 3 months after treatment with
indolebutyric acid (200 mg./l., 5 hr.) (28).

Deuber (24) got 14 and 16 percent rooting of cuttings taken in December
and January from trees thirty years old, 30 percent rooting of cuttings



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