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some species may be at least hastened by treatment. June cuttings of S.
Bumalda var. "Anthony Watercr" rooted 100 percent in 4 weeks after treat-
ment with indolebutyric acid (10 mg./l., 24 hr.), 55 percent without it
(57). Cuttings of S. Vanhouitei rooted 100 percent in 3 weeks after treat-
ment for 8 hours with Hormcnlin A (40 B T I units), not at all without
it (118). Cuttings of S. arguta (80), S. Vanhouttci (14), and 5*. Billiardii
(66) rooted better in sand-peat than in sand.

Stephanandra. Softwood cuttings are easily rooted without treatment. Taken
here in July and August, cuttings of 5*. Tanakac rooted 100 percent in sand
in 3 to 4 weeks whether or not they were treated. Cuttings of S. incisa rooted
better in sand than in sand-peat (14).

Stewartia. Cuttings are taken in summer, often in late summer (106). It is
English practice to make them with a heel (80, 105). Cuttings of 5". korcana
and S. ovata taken here in late July and early August rooted not more than



PROPAGATION OF TREES AND SHRUBS 37

20 percent without treatment but they rooted 88 to 100 percent in sand-peat
in 8 to 10 weeks after treatment with indolebutyric acid (50 mg./L, 20
hr.). Sand (105) and sandy soil (7, 80) have also been used successfully.
To induce more of the rooted cuttings to live through the first winter,
sometimes difficult, they should be kept in a warm place and, if possible,
growing (105).

Styrax. S. japonica is not usually propagated by cuttings (104), but un-
treated softwood cuttings of that species, 5". americana, and 6". Obassia rooted
well if taken here in mid-July, less well if taken in late August. Taken here
in late July, untreated cuttings of S. japonica rooted 40 percent in sand, 80
percent in sandy soil; and those which had been treated with indolebutyric
acid (12.5 mg./L, 18 hr.) rooted 50 percent in sand, 90 percent in sandy
soil. Such treatments sometimes merely hasten rooting. Cuttings of
S. japonica rooted 1()J pe-Ccut in 8 weeks wilhuut h-eatment and in 3 weeks
after treatment (indolebutyric acid 50 mg./L, 4 hr.) (125). December
cuttings of S. americana responded to treatment with 4 mg./cc. applied by
the concentrated solution-dip method (49).

Syiiiphoricarpos can be propagated by cuttings of hard or soft wood (51).
Untreated cuttings of snowberry rooted well when taken in June, July, and
August (44). Similar cuttings of coralberry, untreated, rooted 100 per-
cent and best with the basal cut a half inch above the base of the current
season's growth (46). Late June cuttings of that species rooted, in 3
weeks, 93 percent after treatment with indolebutyric acid (5 mg./L, 24 hr.),
27 percent without it (57). Softwood cuttings of snowberry rooted better
in sand than in sand-peat, better at 70° F. than at 60° or 80° (116).

Symplocos paniculata, Asiatic sweetleaf, has been considered difficult to
propagate by cuttings (98). Softwood cuttings taken here in early June
rooted 58 percent in sand with treatment, 36 percent without it; and
similar cuttings in sandy soil rooted 92 percent with treatment (indole-
butyric acid 50 mg./L, 24 hr.), 55 percent without it.

Syringa, lilac. Cuttings of 6". vulgaris root best if taken in spring, May or
June here, while new shoots are still growing (49) or very soon after
flowering (67, 78, 125). Being very soft, they must be carefully protected
against wilting; but taken later, when the wood is harder, they root more
slowly and usually in smaller percentages (60). Cuttings taken as late as
July are less likely to make good top growth that season (46). Good
cuttings are made of shoots, not too vigorous (106), which are not more
than six inches long (45). Complete shoots, with the basal cut at the
base of the current year's growth (46), root better than parts of shoots
(60).

Lilac cuttings root well in sand (78), better than in sand-peat (44, 56,
116). They should be inserted at an angle so that the leaves are almost
flat on the sand (45, 60). Shading is more than usually important for
such very soft cuttings. Bottom heat has been recommended and cut-
tings of two species rooted better at 70° F. than at 60° F. (116).

The optimum concentration of indolebutyric acid is not exactly the same
throughout the season (cuttings taken early are likelj^ to need a some-
what greater concentration than those taken two weeks later), nor is it
exactly the same for all horticultural forms of 5". vulgaris (60). But their
rooting, and tlie rooting of cuttings of other species (60), is usually im-
proved by treatment with 20 to 60 mg./L, 24 hr., 2 to 12 mg./gm. talc, or,
by the concentrated solution-dip method, 4 to 10 mg./cc. (49). Taken
here in mid-June, cuttings of Marie Legraye rooted 22 percent without



38 MASS. EXPERIMENT STATION BULLETIN 382

treatment, 100 percent in 90 days after treatment with 25 mg./L, 24 hr.
Similar cuttings of Vestale, more benefited by 50 mg./L, rooted 87 percent
with treatment, 36 percent without it. Cuttings of Reine Elizabeth and
Siebold, taken in May, rooted 100 percent in about 4 weeks after treat-
jnent with indolebutyric acid 12 mg./gm. talc (49). Similar cuttings of
S. villosa, S. Henryi, S. tomentella, and Persian, Hungarian, and Himalayan
lilacs rooted not more than 25 percent without treatment, but 75 to 100
percent after treatment with indolebutyric acid (40 mg./L, 24 hr.) (60).
Indoleacetic acid is also eflfective (87), and a treatment of lilac cuttings
with naphthaleneacetic acid (20 mg./L, 24 hr.) was highly beneficial (47).
Cuttings of the variety Mme. Lemoine taken here in early July, too late
for best results, rooted 17 percent without treatment, 34 percent with
indolebutyric acid (25 mg./L, 22 hr.), 48 percent with naphthaleneacetic
acid similarly used, and 63 percent with naphthaleneacetic acid (100 mg./L,
5 hr.).

Tamarix, taiitarisk. Softwood, summer, cuttings root readily in sand (106).
Untreated late June cuttings of T. odessana rooted 90 percent in 3 weeks (57)
and similar cuttings of 7". pentandra rooted about equally well (66).

Taxus, yew. Cuttings of Japanese yew rooted best when taken in Decem-
ber (13), December and January (31), or January (103), but cuttings of
this and other yews also root well when taken in October and November.
August cuttings will root in a cold frame but more slowly than do fall
cuttings in a greenhouse (123, 125). The basal cut is made at the base of
a year's growth, usually that of the current year, but it can be lower.
Cuttings of Canada yew rooted practically equally well when they had
wood one, two, or three years old at the base, but the latter types result
more quickly in larger plants (69). Cuttings have rooted well in sand-
peat (29, 57) ; better, in the case of T. media and Japanese yew, in sand (14,
21, 57). Cuttings of T. media taken here in November and December rooted
better in sand-peat than in sandy soil whether or not they were treated.
Bottom heat, 68° to 70° F., improved the rooting of cuttings of that
species (31).

Rooting of untreated cuttings of yews is generally slow but sure and
the commonest eflfect of treatments is to hasten rooting. Cuttings in the
first stages of dormancy are benefited by higher concentrations than are
those taken later (57). Cuttings of three species responded to treatment
with indolebutyric acid (40 or 80 mg./L, 24 hr., or 12 mg./gm. talc) (61).
Cuttings of a variety of English yew which were taken here in early
December rooted 100 percent in 5 months without treatment, in 3 months
after treatment with indolebutyric acid (75 mg./L, 24 hr.). Cuttings of
T. media taken here in late January responded in the same way to treat-
ment with 50 mg./L, 24 hr. Indoleacetic acid (50 mg./L, 12 hr., or 100
mg./L, 16 hr.) also improved or hastened rooting of cuttings of yews
(21, 83), and naphthaleneacetic acid (40 mg./L, 24 hr.) was very eflfective
with fall and winter cuttings (47) — rather more eflfective in fact, than
indolebutyric acid (58). Naphthaleneacetic acid {2i2> mg./L, 24 hr.) also
hastened rooting of summer cuttings (113).

Thuja, arbor-vitae. Cuttings are usually taken in fall and winter. There was
good rooting of cuttings of American arbor-vitae, made of the current
year's wood with a heel, which were taken here in every month from
November to March, but those taken in and after January rooted a little
more quickly. January cuttings of giant arbor-vitae also rooted well (123,
^25). August cuttings of American arbor-vitae (var. robusta), in a cold



PROPAGATION OF TREES AND SHRUBS 39

frame, rooted more slowl}' but as well finally as did fall and winter cut-
tings in a greenhouse (123). Sand-peat (14) or sandy soil (27) gave bet-
ter results than sand as a rooting medium. Cuttings of nine varieties of
American arbor-vitae responded to treatment with indolebutyric acid (40
to 80 mg./l., 24 hr., or 12 mg./gm talc) (61). Cuttings taken here in
January rooted 100 percent whether or not they were treated (100 mg./l.,
16 hr.), but treated cuttings rooted in less time by about four weeks. The
only eflfect of treatment (80 mg./l., 20 hr.) of October cuttings of the
variety globosa and January cuttings of giant arbor-vitae was, similarly,
to hasten good rooting (125). November cuttings of the latter (var.
atrovirens) rooted 75 percent in about two months after treatment (50
mg./I., 24 hr.), 15 percent without it (57). Such treatments not only
hasten rooting but may also increase percentages which root finally. With
sandy soil as the rooting medium, cuttings of oriental arbor-vitae which
were taken here in December rooted 78 percent with treatment (50 mg./l.,
24 hr.), 2i7 percent without it; and December cuttings of T. occidentalis var.
"Douglasii pyramidalis" rooted 100 percent with treatment, 62 percent with-
out it.

Thujopsis dolabrata, Hiba arbor-vitae. Cuttings do not root readily, but
those taken in summer and treated with indoleacetic acid (50 mg./l., 24
hr.) rooted 45 percent more in 3 months than did untreated cuttings (113).

Tripterygium Rcgelii. Hardwood cuttings taken here in late March, buried
in sand in a cold cellar for a month, and then lined out in the field, rooted
100 percent in 9 weeks whether or not they were treated.

Tsuga canadensis, common hemlock. Cuttings, if treated, have rooted well
when taken in September or October (109), November (24), January
(125), March or April (61), and early summer, although early summer
cuttings, being soft, are difficult to keep in good condition (49, 126).
Summer (49), fall, and winter cuttings of this species (and T. Sieboldii)
responded to treatment with indolebutyric acid (40 to 80 mg./l., 24 hr., or
12 mg./gm. talc) (61). January cuttings rooted 79 percent in 62 days
alter treatment (50 mg./l., 22 hr.), not at all without it (125). Cuttings
of the variety pendula which were taken here in early September rooted 83
percent in sand-peat with treatment (50 mg./l., 24 hr.), 34 percent with-
out it. November cuttings rooted 5 percent without treatment, 65 percent
after treatment with indolebutyric acid (4 mg./gm. talc) (24). November
cuttings of a dwarf hemlock growing in southern Vermont and making not
more than one inch of new growth a year were here made with the basal
cut at the base of the two-year-old wood. Best results and most rapid root-
ing, 80 to 96 percent in sand-peat in 11 weeks, followed treatment with
indolebutyric acid, 100 mg./l., 16 or 24 hr., or 200 mg./l., 8 or 12 hr.,
rather than lesser concentrations. There was at that time no root'ng
of untreated cuttings although all were still living. Summer (44) and
winter (125) cuttings have also rooted well in sand.

Ulmus, elm. Oriental elms (124) and white elm can be propagated by soft-
wood, spring, cuttings. New shoots of Siberian elm, taken when they
were four to six inches long, rooted in 4 weeks (127). June cuttings of
that species and of Chinese elm rooted well in sand (44). Cuttings of
Siberian elm rooted best, more than 80 percent, with the basal cut a half
inch above the base of the current season's growth (46). Cuttings of
white or American elm taken here in early June rooted 94 percent in 5
weeks after treatment with indolebutyric acid (50 mg./l., 24 hr.), 23 per-
cent in 12 weeks without treatment. Cuttings of Siberian elm rooted 60



40 MASS. EXPERIMENT STATION BULLETIN 382

percent in 25 days after treatment with Hormodin A (80 B T I units),
not at all without treatment (118).

Vaccinium corymbosum, highbush blueberry. Propagation by hardwood cut-
tings is well described by Bailey and co-workers (4) and their paper
should be read for details beyond those given here. Cuttings 3 or 4 inches
long are made in late March, before buds begin to break, or they may
be taken earlier in the winter and stored cool in moist sphagnum until
spring. They are made of such of the previous year's growth as bears
no fruit buds and is not too weak, with the basal cut just below a bud,
the top cut just above a bud. They should be set so deeply in the root-
ing medium, sand-peat, that only the top bud is out of it. Untreated
hardwood cuttings which were taken here in mid-March rooted 100 per-
cent in sand-peat in the case of the varieties Rubel and Harding, 50 to
88 percent in the case of Adams, Jersey, and Pioneer. Their rooting
here, as elsewhere (54), was not improved by treatment with root-induc-
ing substances.

Softwood cuttings taken in or about July (44, 53), are made with the
basal cut at or near the base of the current season's growth, with few
or no leaves removed (46). They should be set deeply in the rooting
medium, sand-peat. Rooting of June and July cuttings of Rubel was
improved by treatment with indolebutyric acid (20 to 40 mg./l., 24 hr.,
or 2 to 5 mg./gm. talc) (49). Softwood cuttings taken here in July and
treated with indolebutyric acid (50 mg./l., 20 hr.) rooted in sand-peat
as follows: Jersey, 100 percent in 40 days; Cabot, 80 percent in 35 days;
Wareham, 77 percent in 27 days. Untreated cuttings rooted 50, 2>Z, and
42 percent.

Vacciniufn Vitis-idaea, cowberry. Untreated cuttings which were taken
here in early August rooted more than 90 percent in sand-peat in 8 weeks.
Results were less good in sand or if cuttings were taken in late Sep-
tember.

Viburnum. Spring and early summer is a good time to take softwood cut-
tings. Taken here in late June or early July, untreated cuttings of V. tomen-
tosum, V. rhytidophyllu)!!, V. fragrans, V. Sicboldii, and European cranberry-
bush rooted 80 to 100 percent. Hardwood cuttings of some species also
root well (67). Treatments with indolebutyric acid improve or at least
hasten rooting. Cuttings of V. Carlesii taken here in early June rooted lOO
percent in 7 weeks after treatment (20 mg./l., 18 hr.), 59 percent without
it. Rooting of late June cuttings of that species was hastened by 30 mg./l.,
6 hr. (16). Concentrations may need to be increased if cuttings are taken
later in the summer (83), but rooting of July cuttings of the following
was improved by these treatments : V. tomentosum, 5 to 20 mg./L, 24 hr. ;
arrow-wood, 5 mg./l., 24 hr. (57); V. Sicboldii, 10 mg./l., 24 hr. ; European
cranberry-bush, 10 mg./l., 6 hr. (83). Also eflfective are 2 mg./gm. talc,
or, by the concentrated solution-dip method, 4 mg./cc. (49). Cuttings of
six species rooted better in sand-peat than in sand (14'). Sandy soil is
also good. Cuttings of V. Carlesii, untreated, rooted better in sandy soil
than in sand (27). Cuttings of hobble-bush taken here in mid-July and
treated with indolebutyric acid (50 mg./L, 20 hr.) rooted 67 percent in
sandy soil, 25 percent in sand.

Vitex. Hardwood cuttings of chaste-tree taken here in late March, buried
in moist sand at about 50° F. for four weeks, and then planted outdoors,
rooted 79 percent without treatment, no better with it. Softwood, July,
cuttings of V. Negundo (var. incisa) rooted 64 percent in 22 days after treat-



PROPAGATION OF TREES AND SHRUBS 41

inent with indolebutyric acid, only 4 percent without it (83). Similar
cuttings of chaste-tree rooted 100 percent in sand-peat in i2 days after
treatment with indoleacetic acid (100 mg./l., 24 hr.) (87-). Sandy soil
is successfully used as rooting medium for both species (80, 106).

Vitis, grape. Hardwood cuttings respond to treatments (130), although
less, at least in the case of Concord, than do greenwood, summer and
fall, cuttings. Hardwood, April, cuttings of Concord which had been
treated with indolebutyric acid (80 mg./l., 24 hr.) produced many n.ore
roots per cutting than did the untreated, and a concentration of 10 mg./l.,
24 hr., had a similar effect on softwood cuttings (48). November cuttings
of that variety responded to 40 mg./l., 24 hr.; 2 to 10 mg./gm. talc; or,
by the concentrated solution-dip method, 10 to 25 mg./cc. (49). August
cuttings of muscadine rooted 44 percent in 3 weeks after treatment with
indolebutyric acid (20 mg./l., 20 hr.), not at all without it (125).

Weigela. Hardwood cuttings of a hybrid which were taken here in late
March and immediately set in sand-peat in the greenhouse rooted 90
percent in about 9 weeks, with no benefit from indolebutyric acid. Soft-
wood, summer cuttings, usually root well in sand (14, 44, 105, 106).
There was good rooting of untreated cuttings of IV. Ronbunda taken from
June through September (44). Probably the best place for the basal cut
is above a node (106). Indolebutyric acid at least hastens rooting of
such cuttings. Late June cuttings oi W. florida rooted 72 percent in 20 days
after treatment (50 mg./l., 12 hr.), not at all meanwhile without it; and
August cuttings of a hybrid rooted 95 percent in one month after that
treatment, 30 percent without it (83). July cuttings of another hybrid
rooted 90 percent in 14 days after treatment with 20 mg./l., 24 hr. (57).
Equivalent concentrations of indolebutyric acid for October cuttings of
the hybrid Mme. Ballard are 10 mg./l., 24 hr., or 2 mg./gm. talc, or by
the concentrated solution-dip method 4 mg./cc. (49).

Wisteria, wistaria. Softwood cuttings of Japanese wistaria which were
taken here in mid-July rooted 100 percent in sand-peat in 2 months after
treatment with indolebutyric acid (25 mg./l., 24 hr.), 80 percent without
it. July cuttings of Chinese wistaria, treated, rooted well in sand-peat
(68, 87). Fall cuttings of wistarias will also root, although slowly (124).

Literature Cited

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2. Angelo, E. The use of chemicals in rooting raspberry leaf-bud cut-

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3. Anonymous. Stimulation of adventitious root formation by chem-

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4. Bailey, John S., Franklin, Henry J., and Kelley, Joseph L. Blue-

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5. Bailey, L. H. The Standard Cyclopedia of Horticulture. New

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6. Barrows, F. L. Propagation of Epigaca r opens L. I. Cuttings and seeds.

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7. Bean, W. J. Trees and Shrubs Hardy in the British Isles. Lon-

don. 1929.



42 MASS. EXPERIMENT STATION BULLETIN 382

8. Bean, W. J. The Davidias. New Flora and Silva 1:90-93. 1929.

9. Bowers, Clement G. Rhododendrons and Azaleas. New York. 1936.

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11. Brase, Karl D. Synthetic growth substances in the rooting of soft-

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12 Synthetic growth substances as aids in plant propa-
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13. Chadwick, L. C. Experimental work in plant propagation at Ohio
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14 Studies in plant propagation. N. Y. (Cornell)

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15 Key to evergreen Ilex. Amer. Nurseryman

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16 Eflfect of synthetic growth substances on the root-
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18 and Kiplinger, D. C. The effect of synthetic growth

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23 Propagation of Sciadopitys verticillata with root-inducing

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25. Doak, B. W. The use of hormones as an aid to the propagation of

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26. Doran, William L. Germination of seeds and damping-oflf and

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27 Soil as a rooting medium for cuttings. Amer.

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28 Holdsworth, Robert P., and Rhodes, Arnold D.

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30. Edmuns, Fred C. Camellias return to the front. Real Gard. 2:23-29.

1939.



PROPAGATION OF TREES AND SHRUBS 43

31. Esper, H. C. The effect of time of taking, medium and bottom heat

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32. Fairburn, David C. Plant propagation. Mo. Bot. Gard. Bui. 24:45-

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33. Gardner, F. E. The vegetative propagation of plants. Md. Agr.

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34. Grace, N. H. Physiological curve of responses to phytohormones by

seeds, growing plants, cuttings and lower plant forms. Canad.
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35 Vegetative propagation of conifers. I. Rooting of

cuttings taken from upper and lower regions of a Norway spruce
tree. Canad. Jour. Res. (Sect. C) 17:178-180. 1939.

36 Vegetative propagation of conifers. II. Effects of

nutrient solution and phytohormone dusts on the rooting of Nor-
way spruce cuttings. Canad. Jour. Res. (Sect. C) 17:312-316. 1939.

37 Effects of cane sugar, ethyl mercury phosphate and

indolylacetic acid in talc on the rooting of cuttings. Canad. Jour.
Res. (Sect. C) 17:321-333. 1939.

38 Vegetative propagation of conifers. III. Effect of

month of collection on the rooting of dormant Norway spruce
cuttings. Canad. Jour. Res. (Sect. C) 17:376-379. 1939.

39 , Farrar, J. L., and Hopkins, J. W. Vegetative

propagation of conifers. VII. Outdoor propagation of a Novem-
ber collection of Norway spruce cuttings treated with phytohor-
mones, cane sugar and an organic mercurial disinfectant. Canad.
Jour. Res. (Sect. C) 18:566-577. 1940.

40 and Thistle, M. W. Responses of dormant cuttings of

Lonicera tatarica to solutions of indolylacetic acid and nutrient salts.
Canad. Jour. Res. (Sect. C) 17:317-320. 1939.

41 and Thistle, M. W. Vegetative propagation of

conifers. V. The effect of indolylacetic acid and nutrient solutions
on the rooting of Norway spruce cuttings. Canad. Jour. Res.
(Sect. C) 18:122-128. 1940.

42. Graham, R. J. D. Lawrence Baxter Stewart's methods of vegetative

propagation at Edinburgh. Sci. Hort. [Wye, Kent] 4:97-113. 1936.

43. Griffith, B. G. Effect of indolebutyric acid, indoleacetic acid and

alpha naphthaleneacetic acid on rooting of cuttings of Douglas
fir and Sitka spruce. Jour. Forestry 38:496-501. 1940.

44. Hitchcock, A. E. Effect of peat moss and sand on rooting response

of cuttings. Bot. Gaz. 86:121-148. 1928.

45 Investigations in propagation of particular interest

to nurserymen. Proc. Ann. Meet. Amer. Plant Prop. Assoc. July
16, 1929:28-34. 1929.

46 and Zimmerman, P. W. Relation of rooting re-
sponse to age of tissue at the base of greenwood cuttings. Boyce



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