FR2498894A1 - Herbicidal compsns. contg. lenacil and a urea (deriv.) - esp. for treatment of ornamental shrubs and conifers - Google Patents

Abstract

Compsns. contg. a mixt. of lenacil (I) (3-cyclohexyl-5,6-trimethylene uracil) and a urea (II) are new. The exact nature of the urea (II) is not stated but the title mentions neburon. The ratio (I):(II) is pref. 1:2 to 5:2 esp. 3:2. The compsns. may also contain a surfactant, though more attension is then needed when applied to recent transplantings. Plants that may be treated include berberis, cotoneasters, laurels, ribes, pyrocanthas, roses, heathers, hypericums, azaleas, rhododendrons, etc. and various conifers such as Thuya, Pinus, Cupressus, Juniperus Ginkgos and Larix. The compsns. are selective pre- and post-emergence herbicides active against mono- and di-cotyledenous weeds, esp. those growing amongst decorative shrubs and conifers.

Description

 The present invention relates to a process constituting a selective and pre-emergent herbicide with enhanced herbicidal properties, consisting of a mixture of lenacil and urea. The lenacil is supplemented with a urea, in the proportion of 1/7 to 5/2. It is active against mono and dicotyledons.

 The results obtained by humidity conditions favoring the absorption of lenacil from urea sclution, are superior to those achieved in dry weather.

 This invention can be presented with the addition of surfactant, which strengthens the herbicidal action on perennial broadleaves but requires more attention for recent transplants.

 The present invention relates to the treatment of transplants and seedlings of ages falling into the following categories: conifers and ornamental shrubs.

 The treatment will be carried out on clean, non-clod soil.

 After applying the product, washing the leaves is recommended.

 Invention particularly recommended for the treatment of beds and borders of ornaments.

 Allows the treatment of transplants in containers and buckets.

 These must be composed of potting soil, heather earth or dry bark (not broken down).

 The amount of water required for good spreading of the product is 800 to 1000 liters. In no case should a lesser volume be used.

 The use of the atomizer (backpack device) is completely prohibited.

 The spreading must be carried out using a boom sprayer, fitted with a pressure gauge, which will allow the pressure to be adjusted to 2.5 kg / cm2; maximum pressure allowed.

 Trials carried out in the proportion of 3/2 have proved to be the most effective in terms of selectivity and herbicidal actions.

 However, some transplanting species better support the product in the proportions of 1/1 in filtering soil.

 In heavy soil, after significant rainfall, the 1/2 and 1/3 tests proved to be just as effective, but of shorter duration.

 However, the tests at the above doses, carried out with the addition of surfactant, have been found to be much more persistent, this without adversely affecting the selectivity.

 In pre-emergence, on heavy ground, the dosage of the mixture having brought the best result is 5/2. This is consecutive to the application period when the vegetation to be eliminated is only at the seedling stage and the greater quantity of urea allows very long germination control.

 At all the dosages mentioned, this herbicide destroys mosses, even on containers.

Findings made following tests carried out in 1979 and 1980 in
Renault nurseries in Gorron (medium) and Gérard Letourneux nurseries in Saint Georges Buttavent (Mayenne):
Tests carried out on subcultures and containers.

Treated species: Ornamental shrubs with flowers and conifers including
Ornamental shrubs; Berberis, Cotonéasters, Laurels, Cornus,
Pyracanthas, Roses, Hypéricums, Heather, Azaleas, Rhododendrons, Ribès.

 Notes: Only the Cornus and the Ribès showed necrosis.

 Conifers: Thuja, Picas, Pinus, Cupressus, Juniperus, Cupres socyparis, Ginkgos, Larix and Pseudotsugas.

 Notes: No necrosis noted.

Extracts from the report on the weeding tests carried out at
Guémáné-Penfao 44 experimental nurseries (Ministry of Agriculture).

 Chemical weeding tests in the first year of resinous transplanting.

Description of the tests
The chemical weeding trials 79 in the 1st year of transplanting focused on 2 species.

Douglas 1-0 (Pseudottsuga taxifolia) and (Pin Laricio de Corse 2-0
Pinus nigra)
Soil analyzes of plots C2 and D2 of Guéméné-Penfao (44) -1978
15% clays pH: 4.8 - 4.9
45% total limestone silt: 40% sand Organic content: 2> 2 in C2
1.7 in D2
C / N (Carbon / Nitrogen): 13 in C2 - 1D in D2
The following treatments were applied to fresh soil in the absence of weeds emerged on May 10, 79, to Douglas during bud break and to Pin Laricio de Corse before bud break, at a dosage of 15 kgs of product per hectare treated.

 Irrigation was practiced when necessary, especially during the relatively dry months of June and July.

2. Results herbicide efficacy.

 The results concerning the herbicidal efficacy of the various treatments are collated in the attached table.

Notes - cleanliness score 10 -% weed coverage
10 t of herbicide efficacy compared to control 100 x (treatment cleanliness note - control cleanliness note)
10 - witness cleanliness note
Grassland ratings
On Douglas: After 40 days (21.06.79)
Cleanliness note: 10% herbicide efficiency 100 t
After 90 days (13.08.79)
Cleanliness rating: 9.1 t herbicide efficiency 91 t
On Pin Laricio de Corse after 40 days (21.06.79)
Cleanliness score: 9.7% herbicide efficiency 97%
after 90 days (13.08.79)
Cleanliness score: 8.6% herbicide efficiency 86%
No symptoms of phytotoxicity and no significant mortality.

Conclusion
In the 1st year of transplanting seedlings of Douglas-fir and Laricios pines is selective even on Douglas in bud-break; dose adjustment for improved efficacy should be sought.

 Seedling tests.

 Applied on 4 x 2 m2 shows good herbicidal efficacy (90% at 50 days).

Remarks
At the same doses, was also tested without a device on Douglas in post-emergence treatment (end of June 79).

In the absence of weeds (1 month after diquat-paraquat)
Same efficiency as on Laricio de Corse.

Seedling behavior:
No symptoms of phytotoxicity could be noted in the trial.

 The formulation in micro-granules is only applicable on rooted species.

 The dosages of use are variable according to times and vegetation 40 to 100 kg / h.

Claims (5)

10) Selective pre- and post-emergence herbicide active against mono and dicotyledons, characterized in that it consists of a mixture of lenacil and urea. 20) Herbicide according to claim 1 characterized in that the lenacil is between V2 and 5/2 with respect to urea. 30) Herbicide according to any one of the preceding claims, sensible in that it consists of lenacil and urea, the most favorable ratio of which is 3/2. Certain treatments depending on the time of application and the nature of the soil require dosages varying from 1/2 to 5/2.  +) Herbicide according to claim 1 characterized in that it can be supplemented with a surfactant which increases the herbicidal efficiency while preserving the selectivity. 50) Application of the mixture according to the preceding claims to the treatment of the following shrubs - all conifers as well as ornamental shrubs such as Berberis, Cotonéasters, Laurels, Pyracanthas, Roses, Hypéricums, Heather, Azaleas, Rhododendrons etc ... 60) Application according to claim 5 characterized in that the mixture is dissolved in 1000 liters of water per hectare of surface to be treated.  70) Application according to claim 5 or 6 characterized in that the mixture is sprayed at a pressure of 2.5 kgs / cm2.  80) Herbicide according to claim 1 and 2 for application on transplanting, containers, buckets.  9) Herbicide according to claim 1 and 2, micro-granule formulation, for application to rooted plants.